I think it's an example of how there are two main coping mechanisms of dealing with shame.

One way of dealing with shame is to stay quiet about it, keep your head down and hope that no one notices, and if anyone asks - deny, deny, deny. This is the closeted way of dealing with shame.

The second way is to own your shame. In situations where you cannot plausibly deny your shame, you have no choice but to embrace it. Rather than allow yourself to be judged and ridiculed by others, you will beat the bullies to the punch by making the joke yourself. If you control the joke, then they can only laugh with you, not at you.

When the shame we're talking about is internalized homophobia, we usually associate it with the first type of coping mechanism (i.e., the closet cases). But, I would argue that the obnoxious in-your-face gays that base their entire personality off of their sexuality are just as ashamed of their homosexuality as the closet cases. They just cope in a different way. It's as if they are in a constant struggle to try to justify their existence to the world, and so they overcompensate and turn themselves into homophobic stereotypes.