One thing to consider is your stack size and your opponent's stack size. Your opponent is playing the baby PP in hopes of taking your stack or doubling his stack if it's smaller than yours. If your PFR is less than 1/8 of the smaller of your two stacks or if it's a multipot, he might figure it's worth it. Technically, that's not correct, since he probably wouldn't take your stack unless you both hit the flop, which won't always happen. But if your goal with your PFR is to fold out baby PP, you need to consider this result and adjust accordingly the next time you play this opponent.

I personally think calling 5xBB with 22 is a bad call unless he can count on you to push every time with top pair.

Consider that most of times he's paying you when he plays baby PP (without your knowing it), and you're not pushing your stack every time he hits, and you might feel better about it.