I remember when my oldest used to come home from concerts all bruised and sore! I didn't get it!
we disn't do mosh pits back in the day (the old days)
I've since been to a few outdoor concerts where they've had them. The first I saw was at my own son's performance on stage, so I was really psyched to see "people getting into it". That was mostly guys, too, but it was cool to watch!
Although I still don't get it!
My suspicion is that moshing came about because guys are just too inhibited to dance, so they do this as a substitute!