Why are cars allowed to litter the public roads and park all over the place, taking up a massive amount of space with mostly empty seats and driven around less than 10% of the time?
Also, your comment is a logical fallacy.
Since the majority of places don't have statues for scooters, the default actually is littering, it's no different than dumping anything else on the sidewalk.
Because car owners pay extra in taxes, specifically to cover the additional costs to society.
We massively subsidize drivers in this country. It's a natural consequence of people voting for their own short-term self-interests.
https://www.citylab.com/transportation/2015/05/debunking-the...