That's actually a pretty ignorant way of looking at it. I don't pirate games, I really don't, but I also can't stand people who attribute the cause of rising game prices to piracy.
There are also many more ways to support a game maker than to buy his game. I think selling pirated games is retarded, but honestly, the guys who occasionally download a game, I wouldn't hold it against them too much.
If piracy were an absolute no and there was no way you could pirate games, game sales wouldn't really go up. In fact, they'd probably drop substantially. Think about it, piracy gets spread around, it promotes the game, and several people will, from there, go on to buy it original. That's just how it happens, and the people who pirate in the first place wouldn't be buying the game anyway.
My main position on this is that it is given more attention than the actual motive of making the game. Like, GTA IV made $500,000,000 in the first WEEK of its release. Yeah, the game producers aren't making less money, they're making so, so much more with the expanse network of gamers.