A Little Matter of 20 Cents

I received an letter in the mail the other day from the Port of Edmonds.  Though I had stayed at the Edmonds marina on my first cruise, I couldn't imagine any reason that they'd want to send me a letter.  Did they lose my payment?  Were they angry with me about my liberal interpretation of the "Reserved" signs on the guest dock?  Were they thanking me for all the fame and fortune that my visit brought them?  I hurriedly opened the letter and found this:

Two dimes taped to an invoice.  When I registered at the Edmonds Marina, the moorage fee for Solitude III came out to $19.80.  As I had arrived after the port office closed, I enclosed a $20 bill with my registration card into the after-hours drop box.  I can't say I really cared about the 20 cents that I overpaid, nor was I expecting to get change! 

What I find particularly interesting is not that they returned my 20 cents, but that they spent 46 cents for postage to send it to me!