Not only do I see differences in people's thoughts about this by country/continent, but also by region in the US.
Again, I still don't get why this should be an issue. But then, I don't think people should have a choice about wearing a seatbelt. And I admit, I do say things to others about some of this stuff... one time, when both of my kids were in car seats, I was driving home from work, with the 2 empty car seats in the back. A very young couple pulled up next to me, with a small infant in the arms of the woman. I said something to them, like "get a car seat," and the guy got all crazy and followed me for quite awhile.
Another thing is, why do people think it's OK to insist that children wear helmets, but not for adults? Like our heads won't suffer when we hit them? You wouldn't be upset if your spouse had a TBI, but you would if it was your kid?
It seems like my opinion is in the minority on this thread, and I'm OK with it, but I do get upset with issues of safety, health, etc.