if you want brutal honesty..in the club scene or that general crowd - it is more of a stigma of -
"here is an american , how much can we make off him"
As much as i hate to stereotype- The FSU takes the phrase
"it's all about the benjamins" to a new unheard of level.
If you are going to meet girls at clubs or discos ..
the stigma you asked about of "an american taking our chicks" wouldnt be much worry to you?
as certainly you shouldnt have a hard time meeting girls,
and who cares what the other guys think about it?
you be better off worrying what the girls are thinking, or thier motivations

Any *new russians* in attendence wouldnt worry over an american there as *competition* anyway..they will have plenty of girls around them.
as far as different "social strata" of clubs..
likely the clubs you would be going to are going to be the popular ones.This limits the crowd on hand to the "relatively wealthy" or thier dates, that in itself is quite a bit different than in the west.
as far as "in crowd" at a FSU club - LOL!
forget your western notions,and forget them quickly.
there is only one thing needed to be "in" -
currency.
You did ask about the "real culture" of FSU women,
and i'd suggest that going to clubs or discos in that age range isnt the center of thier activities..
it may be part of their culture as something they might want or "wish" to do often.. or a lifestule they might hope for someday..
I think its more common that the club scene for FSU women is more an occassional situation , than a daily or weekly "norm"
so not sure i'd include it as a big part of thier *Real (daily life)culture*?
I think on average more have bigger worries and issues at hand..
*shrugs*