That's funny. Things can be so illogical sometimes, and people so stubborn. Reminds me of when I ordered something online somewhere, they advertized free shipping over $500, and my order came to $498. Since shipping came to over $30 (heavy) I realized I could add their cheapest item ($8) which I didn't need, and come out ahead. But why be wasteful; I was just going to throw it away or abandon it in a drawer somewhere so I tried to be logical with them and asked them to waive the shipping. They said no, they designed it that way (?)
So I got the order with free shipping and am the proud owner of a set of 4 ugly styrofoam "mug cozies" - well actually they are probably in a landfill by now. I know their shipping cost was over $10 so we both lost on that deal!