Yeah you are right, when i said pet store i was thinking they would be sold as pets.

Though if people are buying feeder mice that are NOT coming from hopefully reputeable breeders, then some of the mice in the cages of small stores probably do have questionable pasts. Little Johnny's pet mice end up with babies and mom takes the babies to the pet store; god only knows what little johnny does with his pets. I had rats as a kid and yes, I took them for walks outside and lost them once or twice before finding them again.