I dont get this joke

[Conian]

Can someone explain it to me? We're all baffled here about it...


Two dogs are in the park.
One dog says, "Man! I can't s**t!"
The other dog says, "You shouldn't've eaten that blind man's car keys!"

[Conian]

Most blind people wouldnt have cars, so no car keys.
Is there something unusual about the keys that blind people do have?

This joke was in the middle of an email full of unusually good jokes.

[Conian]

pokethepope said:

The blind man thought he was giving the dog food but instead they were his keys?

The blind mans car is from the future and drives him around automatically. The dog - a guide-dog - upset at being replaced by a machine ate the keys to prevent the man replacing him with a guide-car?

you're thinking outside of the box there!
sadly the box was labelled 'sanity' and you're clearly outside of it