[locutus2002]

Hero checks because he can't justify a push.

Let's do some dirty math to see where we are at.
Hero bets 2K to win 1K. If he's called he's unlikely to be more than 33% in the hand (generous) so villains must collectively fold 1/2 the time to make this work.

In order for villains to fold 1/2 the time they must each fold ~85% of the hands they would limp with (on average). Because 85%^4=~50%. How much is 85% of the hands villain limps with?

If villain limps any broadway and any suited ace (~230 hands) he would have to fold around AQ or TT to toss out 85% of his limping hands. There is a squeeze factor, and the fact that latter limpers have a much wider range than earlier limpers, stack size, etc, but it still looks like an awful lot of hand for villains to lay down.