There are also an alarmingly large number of Trustafarians in San Francisco who are playing at 'being in a start up' rather than admitting they are just dossing about on a trust fund...
There seem to be a rather large number of those people in London too. Though in their cases, it's often more playing at 'running a company' in general rather than a startup.
Do you have any evidence that it isn't true? :) A wealthy family, if you have one, would be an excellent source of money for a startup.
It's sometimes hard to tell which bits are for real, and which bits are the play-acting, but I've long suspected anyway that more people than you'd think are playing startup. Does it matter if it's with somebody else's money rather than their own? I say no... but of course if your story fits the rags-to-riches American Dream then this can help ennoble what would otherwise be a straightforward tale of simple money-grabbing.