I wasn't really commenting on church structures; I was commenting on the selfish so-called "spirituality" of today's youth that doesn't require religion (and, therefore no need for a church at all; a coffeehouse or lecture hall will do).

But to address your question, I think the more needy a population is, the less it needs a formal house of worship.  But as people become more independent, they need a reminder of that which is more important than their little lives: a place where the majesty of their God is on full display.  When you are rich and no longer have to work...well that's the whole "eye of the needle" story, isn't it.