There's been some vitriol thrown about (on the seagoth board? que lastima!) by people who feel themselves mistreated. Mostly I find it interesting because if I actually went to clubs, I'd probably be one of the cold-and-glaring people being complained about. The majority of the writing is of the 'yes, cold shoulders everywhere, how sad' opinion, or else 'no, people are plenty friendly, or shy' category. I'm sure if I posted how "yep, I'm cranky and don't like to be approached by strangers at clubs" it would just stir up trouble.
I have a tendency to think the people complaining are Not From Around Here. If I had to pick an adjective I'd prefer "reserved" to "cold" but I can see how the two could be confused. I know I don't like to be approached by strangers, but I always have considered it a personal preference. Maybe I should revise it to a regional characteristic, based on this foment...
Of course, I'm the one who saw 32 Short Films About Glenn Gould and thought interacting with people primarily through machines was a grand idea. I think I will continue to try and avoid overgeneralization from personal experience.