Superheroes are an odd breed of characters hell bent on saving the world from some form of evil. Their distinguishing feature is that they wear their Y-fronts on the outside of their lycra bodysuits. But there is a method in this madness: it's to lull their opponents into a false sense of security. A confrontation between Y-front clad superhero and villan would go like this:

Batman: It's the end of the line for you, Dr. Squid!

Dr. Squid: Haha, batman, how can you defeat me when your Y-fronts show that you obviously have no testicals!

BM: That's what you think, Squid. I have in fact withdrawn them into my abdomen to lull you into a false sense of security!

DS: Foiled!

Exit Dr. Squid pursued by a bear.

As you can see the Y-fronts are a decided advantage when fighting crime.