When my girls were little, they went to a Christian school up the road, about 2 miles. The pastor of the church lived 3 doors down from us, and his daughter attended the same school. Every month they would mail the statement, and I'd pay them the next day, when I dropped the girls off to school. This had been going on for a couple years. One month, the secretary met me at the classroom, and asked if I was dissatisfied with the school, having financial trouble, or going to put the girls in a different school. I told her things were fine. What was up with the questions? She explained that I had not paid for the month. I went to the office, asked what I owed, and wrote a check. I assured her I had not gotten a bill, or I would have paid it. She told me she had heard that from several other parents too.
A few days later, the pastor saw me in the yard, and stopped. He asked me if I had gotten that month's bill from the school. I explained I had not, but I did pay. He told me he didn't get a bill either.
Fast forward 2 months. The bill arrived. It had been to Hawaii, Ohio, Texas, New York, etc. It had been bouncing around the country, and had the cancellation stamps to prove it. I took it into the office, to show them. They told me I was about the 10th person that morning that had brought one in, and for whatever reason, the entire batch of statements they had mailed, had all bounced around the country like mine did, starting with Hawaii. No one could explain why, since the zip code was plainly on it.