I understand your point of view.

For me, I find that a cart gives a false sense of safety and when I am a passenger, I am "along for the ride."

When I ride my bike, I am always defensive and have my "head on a swivel" for danger.

for me, they are two different experiences.

We don’t have them. Thought they came on our 2nd cart but went looking for them a couple weeks ago and they were not there. Both my wife and I thought for sure they were there when we bought it but must have been another cart we looked at. Anyway, no belts but I do have some straps for when the grandkids come down.

The simplest solution is in the hands of the insurance companies.
No seat belts used in golf carts, helmets worn for bicyclists or motor bikers in accidents
No Insurance cover.
If people are too dumb to help keep their own bodies in one piece, stuff'em, that's their problem.

Would you order a car without belts?

If a golf cart was used for what it was intended there would be no need for seat belts. However, now golf carts are small cars and can be driven by anyone regardless of their ability to drive, i.e. people who cannot get a driver's license can drive a golf cart!

We have had golf carts try to overtake us in our car on the quieter back streets in our village. We have clocked golf carts doing 30+ mph. They are toys to many people, not vehicles.

IMHO, if you abuse the cart and have a roll over, no one to blame but yourself.