It might be cheaper to freeze, but it's also illegal to do so in the United States. Denying a reptile veterinary care is against federal law every bit as much as denying a puppy the proper care is. If somebody calls Fish and Wildlife Service or a local animal control officer who is actually willing to enforce the laws protectiing reptiles you as a store employee can be held liable for your actions. If I were you I'd make it very clear to the owners of this store that they are asking you to break the law when they tell you to freeze a sick snake. You don't want to risk being fined for something that is against your better judgment and a very cruel thing to do. I should think the store owners would not want to risk all their animals being confiscated or the loss of their business license as that is not exactly economically feasible.
I've been on the other side of this issue, working as a licensed wildlife rehabber I often report pet stores. While I'm glad to see laws enforced it breaks my heart that employees who never wanted to freeze animals are sometimes the ones who get the worst punishment. Please protect both yourself and the animals and refuse to freeze sick reptiles.
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