Nice store refuses to sell gym vest found on the shop floor

This happened quite a while ago but I still feel the need to mention it. I walked into the store to browse and perhaps purchase gym gear. I found a nice gym top on the sale rack. When I went to the cashier to buy it they said that the top was not supposed to be on the floor as it was meant for another store. I asked them to keep it aside for me but was told they could not do that either. The manager went to the back of the store to find out the proper story and returned, apologized and said that the item was meant for another Nike store and he didn't know how it got onto the floor but I couldn't purchase the item. I left confused as why it mattered which store I purchased it from and also what happened to the saying "the customer is always right"? I never encountered something like that before, it was extremely annoying and a waste of time.