An important thing to recognize is that they are not playing bad poker. They all don't play poker, but these are not bad plays. First off the antes are a big reason and second of all the deep stacks. The new Harrington on Cash games series explains this very well. As stacks get deeper the gap between the big and small hand narrows. Think about it, AA is not going to stack with those deep stacks unimproved (without a good read). So when AA as well as 44 have to set to be worth money the gap between them narrows, as the only time their value changes is if there's a set over set.
The small hands are NOT "hoping to get lucky". Well in a sense they are, but it's all about implied odds. In a big-stacked game like that stacking an opponent is huge. And then practically the opposite concept does this as well. Because players are less willing to stack with a big hand it's easier to bluff an opponent off of a hand. Think about it. Low-stakes cash game where the opponent is 60 big blinds deep. I don't care what flops, he's stacking that flop. Now in a high stakes game, say the board pairs, AA would be foolish to stack there. So for that reason bluffs become more able to take pots down. When it's a small hand vs. a big hand the small hand has one advantage in that it knows if it's good or not. If 53 misses the flop, there's no way it's any good. AA doesn't flop a set? You could be up against a set and 2-pair or you could be up against bluffs. The average online player won't be able to lay down the low end of a straight, while a high stakes pro 167 BBs deep would. That's more reason to play those hands, because you can get out of the inherently messy spots these create sometimes, and because even if you don't hit, you are able to bluff others out of the pot if they don't hit a big hand.
And then there is the fact that these are tremendous postflop players. They are able to make good laydowns or good bluffs to escape the marginal situations. Obviously mistakes are still made, but