Am I missing something?

For about 2 months, I've been participating in an exercise class specifically for pregnant women and new moms. We meet in a local park and combine cardio work (power walking, jogging, whatever) with resistance work using stretch bands. Today toward the end of class, we were doing ab work near the playground, and a woman came up with a couple of kids and started talking to the class instructor. Apparently, the woman (Melanie) used to take the class but hasn't been in a while. Anyway, we were all chatting with Melanie and she started telling us about how her 2 year old was acting up the other night when he was supposed to be going to bed, and so she went into his room, "whacked" him without saying a word to him, and left. She was happy to report that he piped down and went to sleep after that. The weird thing was, she sounded almost proud of herself, and from the way she was talking, it appears that smacking her son is a fairly regular occurrence.

Now, I recognize that reasonable minds can differ about whether a mild spank from time to time is an appropriate form of discipline, but among the people I tend to associate with, it's not really accepted. And maybe I'm hyper-sensitive because as a child, my husband suffered some pretty horrific beatings at the hands of his (ex) step-father (not his mom's current husband, but her previous one). So to me, it's totally verboten -- neither Jason nor I have any stomach for physical punishment. But my delicate sensibilities aside, I still found Melanie's almost gleeful recounting of hitting her kid to be repulsive. Is it me? Has it become cool to beat your child?