Not sure where to start about taxes, but for one thing we came pretty close to repealing the gas tax in CA a few months ago so that doesn't seem to be a necessary condition. And some people just happen to pay almost no property tax at all because they got here first (prop 13) but they still get access to all the same schools and fire and police services. Taxes are paid by the public at large, to benefit the public at large, you're not paying for the specific services you're using when you pay taxes. In fact it's exactly the opposite, these things are public goods.
In addition as other comments mentioned, the scooter companies are paying registration fees and taxes. At least in some cities, and I'm sure if they stick around it'll soon be in all cities.
That was a recent increase to the gas tax that was up for repeal, not the whole gas tax.
so while they are licensed, they are certainly not paying market rates for the use of these right of ways.