Yes complain to Walmart but they are not allowed to ask if it is a Service Animal, so anyone can say it is. I was in the lines where the patrons are on the same aisle each facing a cashier. A dog behind me and one next to me got in a fight at my ankles. Scared me and I moved into the main aisle. When I complained she said there was nothing they could do about it. Unsanitary too!
You need to file a formal complaint with walmart headquarters. I don't have any other ideas unless you go to the better business bureau.
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