I always wonder about how all the other trainers in-game start out. We almost never see another starter in battle besides for our rivals... the only one I remember is the Grass gym leader in DPP who uses a Turtwig. Do they just befriend a wild one? Or I guess like in Wally's case, someone else helps them to catch one and that acts almost as a starter. Still, it does seem odd that there aren't massive mobs at the Proffeser's lab trying to get a starter. There should be what... at least a few hundred or thousand 10 year olds in each region? Do they get starters?
In the games it always seem implied you and your rivals were chosen by the region Professor after seeing potential in you. So I don't think any trainer can go to the Professor and get a Starter; they need to prove themselves to the Professor that they're up to the task (also being you and your rival get a Pokedex it seems not only do you need to prove yourself to the Professor but he/she also needs you to help with their research by doing field work).
As for other trainers, my guess they either befriend a wild Pokemon, catch a weak wild Pokemon with a lucky Pokeball throw, or get one as a gift. As we saw with Wally, it seems like your local Gym Leader will help you catch a Pokemon (or maybe even let you be their apprentice/student, Gym trainers got to come from somewhere).
Also I assume the reason the world isn't filled with kids running around is because Pokemon training is hard. We're experiencing Pokemon training from both a meta level and also from the point of view of a trainer who was deemed to have a lot of potential. However the NPCs you see as just money and experience, they're the trainers who somehow managed to break away from the pack and proved they can be Pokemon trainers. Maybe not Champion worthy trainers, but they're still able to train Pokemon pretty well. As for everyone else? Well they'll just go on and get another job. The Pokemon World still needs police, doctors, scientists, constructions workers, merchants, programmers, manufacturers, lawyers, accountants, farmers, and ALL the other jobs that exist. The job of a Pokemon Trainer isn't just becoming Champion but rather to understand Pokemon and keep the peace between them and humans. When there's a wild Pokemon acting up you call in trainers to take care of it. Of course the job has also evolved so that Trainers are also entertainers. They have their Pokemon battle and perform to impress crowds. It sounds like if Pokemon was real that being a trainer would be a tough job.
Unova (Black 2 and White 2) - uh...I can't remember what was said when Bianca gave us our starter...
I think you mother set it up to get you a Starter. She's a friend of BW's mother, being the first Pokemon Nurse who she met. And since BW's mother knows Juniper, she was able to help set things up for you.
The Smog: Mysterious Ghosts?
The newest issue of The Smog is out and it has an article I think is worth talking about. The article is about the real ghosts which appear throughout the games (main series at least). While reading through the article I thought maybe it was worth discussion:
Gen I: Talks about Cubone's Mother/Marowak's Ghost. Not really anything to discuss further. I do have to say that they may be getting their canons mixed up, though. The ending paragraph says:
The ghost of the mother then settled in the Pokemon Tower, only coming to rest once she saw her child again after years of terrorizing the tower.
Except it didn't, we defeated it which helped ease its restless soul. In Pokemon Origins that's what happened, but in the games you just defeated it. Also I question how long Marowak has been dead, I always took it that the death was a recent event. The reason people say the Pokemon Tower is haunted is because the Ghost-type Pokemon disguise themselves as real ghosts (and the Cubone too. Maybe after Team Rocket's invasion the Ghost-types are helping the Cubone by hiding them as ghosts too?), not only because of Marowak's mother.
Gen IV: Talks about the ghosts in the Old Chateau. It reminded me that Charon lived in that house once, so the question is what is his relation to the ghosts if any. The article suggests that the old man ghost is Charon's father/butler and the little girl ghost is Charon's daughter. I'm not too sure if I agree with that, for one thing I think its Charon's childhood home so if the ghosts are related to him the old man would be his grandfather/butler while the little girl would maybe be his sister or cousin.
It also suggests that Rotom electrocuted the two to death but I'm also not so sure about that. I suppose it possible but Charon got electrocuted but didn't get killed. It's on par with the poisoning theory due to their being an Antidote found in the garbage.
Personally I think there's not enough info, we don't know their exact relation to Charon and there's no exact hints to their deaths. And who know if they weren't around when Charon was a kid, I mean there was a Rotom around so it seems at least Ghost-types liked the place.
Gen V: The ghost we actually know most about. First randomly appearing on Marvelous Bridge in BW, only info we got on her is that she used to play in the area with her Abra. In BW2 we got more on her is that she lived at the Strange House (at least at near the end of her life) and found out she was put into an eternal sleep by Darkrai, dying before they could get her the Lunar Wing.
While we know the most about her, there's still stuff we don't know. Like for one thing the article says she may have lived in Black City/White Forest though I think she could have lived in Nimbasa City as its just as close to Marvelous Bridge (heck, she maybe lived in a house on Route 15 or 16). Also it suggests she went to the Strange House after dying though I think she lived there at some point near the end. Though the question is the order of events of what happened. Why did she move from wherever was close to the Marvelous Bridge is to the Strange House (or did she always live there and used Abra to teleport to the bridge and back)? When did she get put into the eternal sleep by Darkrai? Why did the Darkrai put her in the eternal sleep (remember Darkrai did appear to her in her dreams as her father to tell her everything is alright)? Why and how did she die before getting the Lunar Wing, did Darkrai intentionally kill her before she could be woken up?
Gen VI: We talked plenty about the Hex Maniac Ghost in XY who's looking for someone (article suggests the old man in the Spooky House. It's also pointed out the message in Lumiose Station which said "I'm going to go for help. Wait in the usual place." having something to do with her). It also talked about the Ghost Girl in Phoebe's room in ORAS, also mentioning that in the manga it said she had a deceased sister (though once again that is a separate canon so that might not be true in the games. Also the article goes off about how her sisters souls was taken by a Litwik and the Chandelure on her rematch team is that same Litwik. What? Was that in the manga or did the article writer just make a huge assumption). I think we talked in length about the Gen VI ghosts so I don't think we need to talk about them anymore unless the info in the article reminded you of something.
I have my own theories and stories, though I think I talked enough and would like to hear what everyone else has to say.