This is so simple and short but you don't really expect the end. I really liked that. And the bit about the cigarettes is interesting.
In the first two lines the word walk comes pretty closely after the first walk, maybe changing one of them to another word for walk would make it flow better.

-Lorki (from the review marathon- Linky on profile)

wow, great piece. I knew they were SOMEWHERE like a jail or something of the sort, but not really, you know? and then I got to the end and it was kind of an "OH" situation.

lol whoa. That was a nice slap in the face. Man... how did i miss the hints that they're in jail?

Wow, I like this!

It's cool how you can't tell they're in jail until the last line, but when you go back you can kind of see the hints at it.

Nicely written! =)