Anti-Jokes

I discovered "Anti-jokes" this week, and I have to admit, I LOVE them. The teens in my Tuesday evening adolescent program told me about them. Here is the first one I was told:

What is worse than finding a worm in your apple?
The holocaust.

Here are a couple more:

Roses are Red,
Violets are Blue,
I have a gun.
Get in the van.

Roses are blue.
Violets are unicorn.
This makes no sense.
Refrigerator.

What's green and has wheels?
Grass. I lied about the wheels.

Roses are brown,
Violets are brown,
Who crapped in my garden?

If someone could explain to me why I love these so much, I would appreciate it!