Once I found out about that, I would quit patronizing that pet store and I would tell them exactly why. And I would call the ASPCA. Seriously. I'm pretty sure this is illegal for a pet store to do - live freezing is not an ethically acceptable form of euthanasia. It's a painful way to die, despite beliefs to the contrary.Well, I found out they don't pre-kill them, they just put them in a container and freeze them. I hate that!
As far as The Mouse Factory goes, I can't help you there but I'm curious to hear what people say - I'd like to start buying my mice wholesale frozen too.