Because they're funny on many levels.
It's Narnia business.
I'd tell you happy birthday, but to me, you've been dead for centuries
Dan Quayle wrote this joke.
Two. One to post the joke and one to post a better punchline in the comments.
Well that escalated quickly.
He was feeling down
He who makes a mistake in an elevator is wrong on many levels.
I'm gonna level with you.