I've never seen somebody drive a car on the sidewalk.

I see scooteridiots going 15+ MPH on the sidewalk all the time.

We don't have them in my city (thankfully), but in the cities I've visited most of the people using them were teenage joyriders who would otherwise be walking.

To purport that these people drive cars and ride scooters in the same manner is unfair. Same with bicyclists - I witness dozens of them running stop signs and red lights every single day. Can't imagine they do the same in cars.

You don't need a license to ride scooters. Yesterday I saw a gaggle of preteens riding a squadron of scooters.

Incorrect. In London they replace people getting trains for the most part. They also make flagrant use of pavements.

Somehow I doubt that where you live, those "two ton death boxes" are often driven on a sidewalk.

If scooters keep to the road, they are perfectly fine. When they drive on sidewalks, eventually one of them will be biting my elbow.