I see a lot going on within the thread. To clarify some things:
When I attended the first group run I din't know anyone from the group thus I didn't have any info of cliques, if two people are friends, between others may be a hate relationship, etc. Also there were some runs with no remarks so I thought this was settled between members or it was an isolated incident.
Later I found out that the guy with the compression socks remark has a daughter a few years younger (early twenties) than the girl in compression socks (late twenties).
The running scene within the town is not too developed and this is the only club. However no new people are showing up now and there is a decline in attendance. Meanwhile I see more and more people running in the parks even at freezing temperatures.
I know some clubs may have a niche, however I don't recall any club branded as butt, lingerie, compression, etc. running club.