We're doomed: authorship question edition

Ads have started popping up on campus for Anonymous, a new movie advancing the stupid idea at the Edward de Vere, 17th Earl of Oxford, who died ten years before Shakespeare died, is the real author of Shakespeare's plays.

The authorship question has always struck me as the most pointless species of coffee-shop bullshit, given that there's no reason to think Shakespeare didn't write those plays. No reason, that is, except chauvinism: the belief that only a member of the genetic aristocracy could possibly write fine plays.

As it happens, I just read Bill Bryson's Shakespeare book last month. The final chapter is devoted to this trumped-up controversy, which he entertains and dismisses more concisely than I ever could. His discussion culminates on page 195:

[It] is possible, with a kind of selective squinting, to endow the alternative claimants [the Earl of Oxford, the Earl of Derby, Francis Bacon, Christopher Marlowe, and others] with the necessary time, talent, and motive for anonymity to write the plays of William Shakespeare. But what no one has ever produced is the tiniest particle of evidence to suggest that they actually did so. These people must have been incredibly gifted-- to create, in their spare time, the greatest literature ever produced in English, in a voice patently not their own, in a manner so cunning that they fooled virtually everyone during their own lifetimes and for four hundred years afterward. The Earl of Oxford, better still, additionally anticipated his own death and left a stock of work sufficient to keep the supply of new plays flowing at the same rate until Shakespeare himself was ready to die a decade or so later. Now that is genius!

What is it about the allure of conspiracy theories that makes otherwise smart people stupid?