I think the craziest one i have heard was at a petco. Im walking through the herp area looking for some thing, when i over hear an employee trying to sell a young lady on a leopard gecko. As i walk past the area they are in i hear the male employee saying "yeah the grow to over 2 feet. They also require temps over 110F in order to survive..." I could take it i had to walk over and alert the young lady to the fact this "expert" was a moron. I showed her a web site on her phone where she could find a proper leopard gecko care sheet and gave her options of where to buy an actual baby leo(they had full grown adukts marked as babies).
On my why out a manager came up to me to lecture me on interupting their sales staff while making a sale. I calmly explained i would never have interupted if ANY of their staff new anything about reptiles.or other herps. That he also should be ashamed of himself for hiring people to head up a reptile area who knew exactly nothing about the animals they would be caring for and selling. He then threatened to ban me(no loss here useless place anyway) i said no problem, but i would like corporate phone number. I returned a week later to find the store was under new management, and all but 3 of the original.employees were fired along with him. Turns out he was hiring his friends to hit on female customers.
The chain places always seem to give the most and best of these stories...