Yes, the price goes up quite a bit but I think it pays off in the long term. I think those bikes are especially interesting for people who just want to go from A to B and don't consider themselves "cyclists" (aka use it for sport). Add some puncture-proof tyres and you have a bicycle that will most likely just regular maintenance once a year.

That said, when something does go wrong with the belt/drivetrain/hub it becomes a pain in the arse.