...Until he gets laser eye surgery. After that, he's just wears them out of habit.
Parodied: Bob wears multiple pairs of glasses at once, thinking they'll make him look very smart.
Zig Zagged: Bob puts on a pair of glasses and ends up acting like an idiot. Later it is revealed that they were cursed and once removed Bob ends up acting smarter than he was precurse. However, once Bob ends up getting it destroyed he ends up even smarter.
Exploited: Cassie sells nerdy-looking glasses to college professors who don't need them, figuring they probably want to look smart.
Defied: Bob wears contacts and is still pretty smart.
Discussed: "Watch him whip out those glasses later in the show."
Conversed: "Do all glasses imbue people with great intelligence?"
Bob wears glasses so that he'll look smart. People don't fall for this and Bob is ridiculed and looked down upon as a result of his charade.
Bob wears corrective lenses (and doesn't need them) so he'll come off as more intelligent. He wears them so often that his eyes are conditioned to wearing them, to the point where he needs glasses in order to see.
Bob's glasses are magical and boost his intelligence when he wears them.