I've seen this a lot. It's not the amount which has been bet but the fact that someone has bet or raise/reraised them which throws people off a hand. Basically they are playing their cards and not thinking beyond that, correct?

A question on your play. I understand the call preflop but why did you just proceed to call the bet and call on the flop? Was it because of your kicker or was you planning on doing a bet/raise on the turn if both players slowed down? Would you have just called a turn bet here? At what stage (if any) would you have considered to fold?