Pet shops tend to bunch animals together, and also often buy baby rabbits which are too young to leave their mother/littermates, so the chanced of sickness or stress on a baby rabbit from a pet shop is higher than when a rabbit is purchased from a good breeder. read more
Plus, if you get your rabbit at a pet shop, u have to do all the butchering and stuff. LoL it might even be illegal to get em from a pet shop. Probably more expensive anyway. read more