Someone on one of the truck forums I am on told the story of buying motor oil at Walmart and discovering that it was used oil returned a refund.
Is there no low to which we cannot find a way to debase?
Last time I stayed at the Westin in Boston I opened a beer out of the mini fridge in the room. You know the Heineken that costs $6.00. I took one slip and then spit it out into the bathroom sink. It was water. Some scumbag had drank the beer and then refilled it with water and put the cap back on. I left a note for the maid. I still got charged.
That is why the newest mini frige room bars have an electronic reader that states ANYTHING removed from this fridge will automatically be charged to your room bill.