Not that this is advice, but kind of ridiculous none the less...
I once had a chain store employee tell me that I couldn't return a pair of guppies because they were still alive. Which is understandable, you don't want to catch any disease in your tanks, but I had only had them 2 days and explained that they had been in their own quarantine tank.
She looked at me like she had no clue why a QT was, and said "sorry, it's still against policy" my reply was "so, you can take dead fish, but won't take back live ones that you are able to resell? Would you prefer if I went back home to euthanize them an bring them back tomorrow so that you can do a return for me then? They simply won't work out in my tank and they have to go somewhere." Not that I'd actually euthanize them, I was just tryin to make a point. Finally after I said that she allowed it.
Then her coworker came over and looked at my bagging Job and saw that it didn't have the stores labeling on it. He asked me if I just went out and bought them somewhere else for cheaper and return them there to make a profit. I was like "yeah, the whole 0.50 I could get on 2 guppies would really be worth it!" (Sarcastically) He asked "then why are they bagged so nice?" .. "Hmmm, maybe because I breed and ship fish" he kind of scoffed and acted like it was impossible to ship live fish but didn't say anything to me after that, and I really wanted to say "how do you think you get your fish in?" But refrained because by then the original girl had processed my refund and I just walked out and haven't been back since lol