AA win percentage is the best of all starting hands (at least that's my understanding, however bad it may be). If you fold that hand, you're risking that you never see an actual playable hand for another 5-10 hands, after which the blinds have eaten you alive. You could steal, but if you're not willing to push all in with AA, then you're liable to probably not attempt a steal with two, desperate low stacks without a great hand (which AA would be, to steal blinds or steal an entire stack). I mean, from what I understand about strategy late in tournaments, and what I've experienced, people steal a lot of pots with hands that are far worse than AA, things like K7+ suited, A2+suited or A7+os. If you have AA, and raise all in, anyone who calls is probably holding another really good hand such as AJ+ suited (or even off suit, i've seen it plenty of times) A9+ suited, which you have beat bad. If they have pocket pair, and decide their 88 is worthy of an all in stand against someone who first raised all in from bad position, then you can't do anything about a bad play or a very risky play or whatever you want to call it. I'm no final table pro, but I do know statistics and probability well enough to tell you that the chances that any pocket pair has of hitting their trips is the SAME as the chance your AA will hit trips. Nothing in life is a 100% garantee to win or be right, and poker is definitely no different.
I'd rather lose making the right play, than win making the wrong play. Yea yea, people will laugh at me and mention the money, and I agree the money is a huge factor, but to be honest, not only will I probably lose that extra money I won in the long run by making a bad play and winning because of bad or inconsistent play. Yet, the dude who pushed with AA there, and lost 300k because of it, will probably make back all of that money in the long term if he plays consistently well. Not to mention, I'd rather be the guy who was known to lose to a bad beat, then the guy who only won because his bad call was saved by a lucky draw. Reputation is a bit more worthwhile to me than money, because I enjoy playing the game of poker for more than just getting a ton of cash (although the cash does make poker more exciting and rewarding for playing well =P)