Actually, Rapid Spin is a relatively bad move, if only for the fact that there is a move that obviously out-classes it. SR, or any other entry hazard move.
Let me put it this way: Each turn is an opportunity to accomplish something for your team. In other words each turn you are paying the cost of 1 turn in order to forward your strategy.
If the opponent uses SR, and I later Rapid Spin, here are the benefits each player got:
Rapid Spin: I got one free turn (the turn my opponent used to set up SR, which I later got rid of)
SR User: I got one free turn (the turn my opponent used to get rid of SR) + Some Damage from setting up SR
I realize this is definitely an over-simplification, but it holds true at the basic level.
In other words, it is clear that in terms of cost/benefit analysis, Rapid Spin is inherently inferior to simply setting up your own entrance hazards. The only time Rapid Spin actually gets better cost/benefits is when it manages to get rid of multiple hazards (which quite frankly is rare).
Also it's reliability is questionable as Tay mentioned. If I design an offensive team with few SR-weak pokemon, and that is meant to sacrifice the SR-weak ones early, I can be almost completely certain about how much effect SR will have on my battles. If I have many SR weak or 4x SR weak pokes and rely on a rapid spinner, I really don't know how much an effect SR will have on the battle, because I can't be certain I will succeed in using Rapid Spin or that the turn I spend doing it won't cost me the game (like him setting up DD on the spin or just killing a critical poke).
Now considering opportunity costs (obviously rapid-spinning the incoming celebi is worth a lot more than close-combating it) mean that it is not a bad move, it just is not a really good move, and certainly not a necessary one.
If this is true, then what is the counter-argument for not banning Stealth Rock? I am sorry, this is a little off topic(not really though). I know it holds Gyarados and Salamence in check, but like I said before, if they are only being held back by SR, then they should probably be suspects themselves.
I however, do not believe what you said is true, and I think Rapid Spin has far more benefits than you believe. First of all, everyone tends to do calculations with the inclusion of SR, because it has pretty much become a normal battle condition, however, when you take that out, now they can't rely on their CB Scizor to revenge kill your DD Salamence, meaning you can sweep their entire team, and for what? They got an extra hit on my Hitmontop which can't be OHKOed by anything except Explosion, CB Brave Bird, and Specs Psychic? I consider that an advantage in my direction. If I manage to spin away their rocks against something like a Salamence, I can just send in my Mamoswine and revenge kill them. Now they send in something, possibly freeing up a switch for my Salamence, who isn't taking 25% health anymore. Shit, I know it is a lot of theorymon, but I have tested this quite a few times, and I can infer from your posts that your ideas are theorymon-it DOES work.