Is it just me?

I chaperoned a school dance yesterday after school. This is a middle school, so the youngest kids there were about 10 years old, and the oldest around 13. I must be getting really old, because I was (and still am) horrified at what I saw and heard. The girls all learned how to dance watching MTV and VH1, so when they weren't shaking what they have of chests, they were swinging their little booties back and forth like they meant business. Some of them danced exactly like the girls in the hip-hop videos. It's bad enough to see grown women doing these things. It's very disconcerting to see a ten year old do it.
I don't know if my principal is completely clueless about music or if she just decided to ignore it. The DJ played "Promiscuous" (I can see you with nothing on, feeling on me before you bring that on) followed by SexyBack (I’m bringing sexy back, Them other fuckers don’t know how to act, Come let me make up for the things you lack, Cause your burning up I gotta get it fast) followed by London Bridge (I'm such a lady but I'm dancing like a ho (Oh, snap), 'cause you know I don't give a fuck so here we go! (Oh snap)) and many more. Is it just me, or is this completely inappropriate? The other teachers didn't seem to think anything of it. If it were a high school, it might be ok, but I wonder if the parents of these 10 year olds know what they are hearing?