A New Challenge for Pirates Online Forums!!!!

[Mr. Skiperdoo]

Alright, here's my best shot.

A man walks into a store and buys a shovel for the price of 15$ when it's usually priced at 30$. The man behind him sees the other man walk off with the underpriced shovel, and he knows a good deal when he sees one, so he decides to buy a cheap shovel as well. But unfortunately for him, the cashier says that the shovel can only be purchased at 15$ with a purchase of 40$. However, the man has only 30$ with him, so it doesn't seem possible for him to buy the shovel for 15$. But soon the man has an idea that gets through the problem, and before you know it, he walks out of the store, shovel in hand.
Also, he bought the shovel for 15$ not 30$.

How did he do this? The solution probably won't work in real life, but it's good to ponder.