If you do your research then you will find that medium to large public bodies are especially good at getting ripped off buying these bonds.

Usually your local education board or city council (A) has some money to invest or some income to smooth out. 1. They talk to financial advisors (B) who give advice. 2. The advisors get commissions if they sell certain types of products. 3. The inexperienced financial staff in A believe the advice given by B. 4. The taxpayer shoulders the risk.