Though you have a valid point, an injury to an individual due to their own disregard of the range rules doesn't accrue to the range's liability, it accrues to the individual as personal consequence for their disregard.
There has to be some flexibility and common sense in range rule enforcement. If that deaf individual I mentioned in a previous post had been kicked off the range for not wearing hearing protection I would have considered going elsewhere to do my shooting.
As an example of common sense rule enforcement, it's the rule about not shooting over the berm. That's common sense because who knows where the projectile goes and ends up and so could easily adversely affect some other person than the shooter or some other person's property. Someone that shoots over the berm should be kicked off the range. It's not a matter of a choice that affects only the shooter.
WRT to seat belts, that's a law, and laws are to be obeyed. IMO it's a stupid law as whether or not someone wishes to have their skull crushed in a crash should be a matter of knowing the facts and making a personal choice to wear seat belts or not. Personally, I wore a seat belt long before it was required by law because I chose to protect myself as best I can. But because wearing or not wearing only affects the individual, I think making it a law is an overreach. The law should require seat belts be installed, yes, but usage should be an individual choice.
There's too much shifting of blame from individuals' responsibilities to any other insured targets of litigation opportunity in today's world. It's nuts.