What's the difference between a hooker and a burrito?
I don't eat burritos.
Listen up, you silly goose! The "joke" is that the person answering finds hookers so repulsive that they won't even consider eating a burrito because it reminds them of a hooker. It's a dark joke because it implies something gross about hookers... and you probably are not smart enough to get it. You definitely eat burritos though, I can tell.