I can tell you how these are used in Prague because I've almost been hit by them multiple times while attempting to walk on the sidewalk.

They are used by tourists that don't put in the minimal effort to understand the extensive and very effective tram and metro system. They are usually ridden on sidewalks which is against the law. They are ridden without helmets which has caused a huge uptick in hospital visits.

Basically we are all subsidizing the treatment of injuries caused by these fucking rental companies which provide no net benefit and defund our excellent public transportation. Meanwhile we have to play frogger every time we get on the sidewalk because tourists are riding these things illegally all over the place.