[quickthrower2]

Like taxi medallions?

[CPLX]

Yes like that.

Also notable, the airlines pay for the gates and the landing slots and so on.

It’s a transportation hub. The various forms of transportation that use it pay a fee.

[quickthrower2]

My point is: you are right but Uber has been known to skirt the law.

[skeeter2020]

and every single passenger also pays an extra fee unrelated to the actual act of travel, the airport improvement fee, aka a tax that's not a tax.

[CPLX]

If it’s a fee that’s only charged to passengers who are traveling then it’s related to the act of travel.