[helpmeout]

This is how I see it in very basic terms.

You have top pair, if the game finished preflop you would win.

Everyone else is playing catch up and they have to pay to beat you. You dont need to hit anything on the flop but they have to get at least two cards to beat you.

The flop might come K72r, odds are that a few people might have 1 pair. They are still behind you, thats why you bet.

We can look at it from another hand, our good friend 72o. You have no flush draw or straight draw. If you get one pair it is pretty useless. Odds are that someone will have a higher pair and they will make you pay to beat them. You have to hit 2 cards minimum to have a chance of winning vs AA who doesnt need to get any.