Definately dont have to play sets fast, but its probably correct for that to be your default. Like, lets say you have 44 and the flop is 47Jr. If you raise up this flop, he's only continuing with AJ, QQ+ that you beat. Maybe slightly weaker, but without being able to put you on some kind of draw your range is damned strong.

Most people I play against are like iopq and way to ready to stack off with TP type hands on drawy boards, so I just get them in on the flop the easy way unless I can find a good reason to do otherwise.