I disagree, by that reasoning we shouldn't allow people to engage in dangerous activity either.
Let's start by outlawing mountain biking, sking, skydiving and scuba diving (Etc)
Why stop there? let's outlaw soap in the shower, that's too dangerous!!
We might all smell like the French but we'll live longer.
I think people engaged in those kinds of activities cannot be killed or injured by another person.
The problem with seat belts is that if someone is not wearing them, they can be hurt by someon else (and then they can sue).