I'm just amazed the NTSB allows bus and train passengers to be up in the aisles all the time, anytime, and many of those vehicles don't even have seatbelts.

Look at school buses for instance. They flip over with kids on board all the time, but where's the NTSB to require seatbelts and a B/A, to yell at the kids to please be seated while the bus is in motion?