facebook beginning in college can be explained because its creator was in college at that time, and is natural to expand in your habitat. Sometime young people

facebook beginning in college can be explained because its creator was in college at that time, and is natural to expand in your habitat. Sometime young people copy old habits of old people, so I don't see any trend. The power for expansion is in the marketing, very creative people selling water vapour (in Spain people now smoke water vapour since the prohibition to smoke in public places).