I'm unsure about that, unless you've literally been hiding under a rock, there was full footage as well as commentary and even people trying to get math-ish data available of the demo everywhere.That only works if the game is good. I was skeptical of the Go mechanics, and playing a demo version of it would've made me hate it, though I would've saved some money.
I have a hard time imagining what you could have seen from playing the demo yourself that it wasn't already shown on the 10 thousand videos that were around :P
(also, consider the demo was only upwards to Pewter Gym. Nothing else.)