Why Don't Buses Have Seatbelts?

Government agencies have encouraged us to buckle our seatbelts for 50 years now. Seat belt use is now the law in every state except new Hampshire ...for cars. Buses are exempt, and most of them don't even have seat belts. That sound hypocritical, since governments operate an awful lot of municipal and school buses. What's the deal? Cheddar explains why buses don't have seat belts. We could make buses safer than they are, but the law of diminishing returns kicks in at some point. (via Digg)