There's a running gag in dice-and-paper circles about gaming store owners and employees not wanting to hear about customers' characters.
It's amusing because it's traditionally all-too-true. I've never been employed by a gaming store, but on my infrequent visits I, too, have found myself enduring an annoying customer who takes my passing interest in all things RPG as license to launch into a four hour diatribe about their "awesome" character, their back story, and detailed enumerations of everything they have done on every adventure they've had since first level. Unfortunately, offering a polite, "That sounds cool," and hastily walking away from them often only serves to encourage them to follow and continue their exposition.
Game Masters can be just as bad. They can expound upon their world / campaign as lovingly and at such length as if it were their own child. Only a historian or accountant could have such a love for timelines, details, and numbers. They are Cliff Clavins of their own worlds.