Signing petitions to change the laws would be the beginning of a public safety campaign and more seats plus more affordable seats coming on the market. You don't bury your head in the sand and say it's too hard or too expensive or not practical.
Car accidents and improper use of carseats are one of the leading causes of death in children. We support vaccination campaigns so why would we have a problem supporting this?
Eta: A rearfacing infant/child is 5x times more likely to survive an accident than a forward facing child. It's a fact. Their spines aren't mature enough to support their heads in the force of an accident. Weight and length has nothing to do with it being safe to turn them, a chubby 6 month old's spine isn't any more mature than a thinner child's.