Before you go that route I'd simply suggest speaking directly with the store manager to get a read on whether he/she is truly interested in being a responsible person. Depending on the store size sometimes the management cannot check every snake and depends on employees to do their jobs so start out first seeing if the manager is aware of the situation and is willing to address it quickly. Once you have that conversation you can then decide how to proceed. Remember as well, if this is a chain store, you should always report poor practises (especially if you point them out and they are not addressed) to their corporate head office. You may not get a great response from corporate but you then have a paper trail to show to the humane law enforcement folks.

We had a pet store here that wasn't doing a good job last year and it was getting worse. My husand and I raised issues with the store manager. I'm sure other customers did as well. We were polite but very firm about what we expected them to do for the snakes that were obviously ill. They seem to have done a complete turnaround and are now one of the best stores in town with lovely clean enclosures and healthy stock. The trick is to talk in a professional manner, not emotionally, but with firm purpose.