The scooter company who provides the scooters? The scooter renter who drops the scooter in semi-random locations? The city who built the sidewalks?
It seems like you are targeting the scooter company when it may be the users who are being careless. I’ve seen a lot of scooters left in the way when a reasonably clear area was just a few feet away.
But to address your valid question, the scheme shifts the costs to the scooter provider who would likely then impose costs on the scooter polluter. Although they may instead choose to impose costs on all their customers to subsidize the offender.
But it is a very clumsy scheme with many flaws, so probably not a great model upon which to iterate.
In particular, they could achieve this by enforcing the law that makes them illegal to drive on the sidewalk. It won't matter that it is 3am and the nearest pedestrian is two miles away, or that you're driving at less than walking speed. You'll get fined anyway.
To add a bit of optimism, maybe these systems will become good enough to only fine those who drive inconsiderately or dangerously, and a successful campaign will make that the law, instead of the blanket ban.
It is not enough to kick over a scooter. We need to tag repeat offenders and increase the severity of the response. For instance, paint one handlebar grip on the first infraction, then the other grip on the second, then a seat, headlight/taillight, etc. A scooter that has been tagged enough can have the tires flattened, spokes broken, etc.
Clearly, there are numerous flaws with the solution above. It's really a terrible idea. To some degree it shows the flaws with kicking over offending scooters.
Alternatively, you could hire enforcement officers to issue citations. That also has flaws. You could build a system that allows random citizens to document offenses in a credible way and then have authorities act on repeated offenses. Also not without problems.
Perhaps coloring the scenario differently might help. Imagine, for instance, that a certain neighborhood house is popular with the neighborhood children. The children frequently ride their bikes to the house and leave their bikes strewn in the driveway, the front yard, and on the sidewalk. What would be an appropriate series of responses? How could you build a system that protects against a grumpy neighbor abusing whatever escalation mechanism you devise?