Heartbreaking......:(

[WingedWolfPsion]

Take the photos, and send them to CORPORATE. Go over the store manager's head. Tell them that if they don't act, you're planning to make a fuss and post the photos, because if this is how they treat their animals, the world should know.

Petco corporate doesn't hate animals, and they aren't completely heartless. The problem is individuals, and if you put a bug in their ear at corporate, it's a lot more likely that something will get done about it. Particularly if you tell them it's an ongoing problem.
Mention the lack of hot water as well. It's hard to imagine anything being properly cleaned without hot water, as well as the issue with thawing rodents for the snakes.

They're a big corporation, and they have a lot of inertia--they had a vet write up their care protocols, and unfortunately, he just wasn't enough of a reptile expert to do it properly. Since a vet told them to, now it's hard to convince them to change. They do think they're doing the right thing.

The only way to get them to fix it, is to keep at them over it. Be polite, be reasonable, but be resolute and definite.
It can work, and has worked.