Look, if you can't afford it (or cba to sacrifice other luxuries to save money), don't buy it.
But don't use that as an excuse to download or copy a game.
(I can't buy a dodge viper, so shall I just go steal one?)
The only reason prices are so high are because..well, guess what? A shitload of money is lost on those that just download it.
So don't act like the victim when you're clearly the one doing the crime - saying crime in such a context makes me laugh

though technically, it's still stealing.
As for stuff like WoW, you pay for the service and added content.
It's not just a game that's finished and the developers don't have to spend time, money and talent on anymore.
You're constantly buying new content and service for - what is supposed to be - a low initial price for the game itself.
Sure, 'normal' games have patches (bugfixes) and whole new sets of missions, chapters, maps or models, but while the former just contain bugfixes - which meant the product they sold you wasn't finished before it hit the shops in the first place..tsk tsk! you already paid for bugfixes! - the latter is usually done only once or twice, and definitely not evere half-a-month, and are usually never of as much quality and quantity as in MMO's.