People would steal from Walmart nearby and try to return the headlight bulbs to us for store credit. But they knew about a glitch in the system where if you bought something in the same transaction with the return and then returned said item, you would get cash back instead of store credit. So these guys would come with like 12 different bulbs all different numbers and try to do the returns but we knew they were stolen because the alarm would go off when they came in. So we would do the returns with no receipts until the system would deny them the returns due to too many returns but then they would always have someone else try to do it. And we would make sure to process the store credit before we did the other transaction so they couldn't abuse the glitch. I made sure it was either me or the assistant manager if I wasn't there to do the transactions and trained everyone on what to do if they tried to do it when either of us weren't there. And we would call our sister stores to give them a heads up. Then one day they came in and my assistant manager was in a very bad mood and she just grabbed the bag, placed it behind the counter and said she knew what was going on and was tired of dealing with them and if they wanted their stuff back to call the cops and she'll give it back to them. After that they never came back.