At Starbuck’s today, I ordered a client a tall decaf (don’t tell him) along with some other drinks. When the barista went to pour the tall I realized this was the smallest size and I told her I really wanted a grande (read medium). I went to get out a quarter to pay the difference and she told me not to worry about it. Because she knew that it would take more time to void out the first transaction and run it again and that time was not worth the 20 cents.
This is similar to a rule we had when I worked for a mail order sporting goods company. The owner had wisely figured out the cost of processing an order. He then made a rule that any product under $10 that was misshipped was to be reshipped with no return due from the customer. He knew that the aggravation to the customer to have to mail the item back to us (most often a t-shirt at that price point) and the cost for his staff to process a new order and process the return to stock was not worth it. It was a much better policy to tell the customer to give the incorrect sized t-shirt to one of his friends and look for his correct size t-shirt in the next few days.