I used to work at a record store, and signed up for their insurance plan. It was not very good, and only took a small amount of money off prescriptions and doctor/dentist visits, but it was better than nothing and I couldn't afford a better plan. I was supposed to get my wisdom teeth out last fall and showed up to the preliminary appointment to have them take x-rays and talk about logistics and such.
After I talked to the doctor I went up to the front desk to schedule the surgery. There were two women working at the desk, and I handed one of them my insurance card. She told me she would phone the company to find out what my co-pay would be for the surgery. A minute or so later she got off the phone, wrote something down and showed it to the other woman at the desk. They both burst out laughing. She then told me that it was only going to be $100 off the surgery or something. They started laughing again, as though it was a joke. "This thing is basically useless!" she said, handing me back my insurance card.
I really didn't find it very funny, and I decided not to get the surgery done after all. Yes, the card is basically useless - but why on earth would you say that to a customer?