i'll say something about detroit, though.
for such a large city, the various scenes are very small. maybe it's a reflection on the broader demographics; there's millions of people here, but it's the same few dozen people at all the psych concerts, the same few dozen people at all the goth clubs, the same few dozen people in the techno scene...
i listen to lots of types of music, so i get around. lots of very diverse people are going to recognize me. and the city seems a lot smaller than it is.
even in ottawa, a much smaller city, i'd go out to the same couple of bars all of the time and meet all kinds of different people; in detroit you can go to five different bars on five different nights and get the same group of people collectively bar-hopping for the bands.
and, i guess that's why so many places seem so empty when you don't go to the right party. if all the psych kids are at bar x, bar y could literally be empty - because there doesn't seem to be enough concert goers or general bar patrons to accommodate them both.
it's not too many bars. it's really not. not for the population, here.
it's just kind of a sleepy town in a lot of ways.