Good luck getting states to change their laws anytime soon. Ironically enough, car seats aren’t required on buses not because they aren’t needed, but they would cut off the poor with kids completely from transportation.

Also probably helps that public buses are really really safe statistically.

The driver is regulated at the state level. Safety standards for vehicles are regulated federally.

They’re already statistically unnecessary for toddlers on up: http://freakonomics.com/2005/07/09/more-evidence-on-car-seat...