>>104410803Because he's a well-rounded character.
He gets to kick was just as often as he gets to be the butt of jokes; he's like a cool gay uncle who will take you to some bitchin nightclubs, not a whinging gay classmate who will lecture you about social justice.
Shore Leave is one of the guys, not a diversity hire. He's out and proud but you could basically write him as the same kind of bombastic, sassy dude if you made him straight. He's like the Michelangelo of the OSI, only he likes cock instead of pizza.
Shore Leave's involvement in an episode doesn't start and end with tasteful relationship drama with Al, which is why he works while so many other LGBT characters fall flat. He actually has shit to do aside from just be gay.