They do burden the airport to some degree though. The airport allows off-airport rental agencies to drive their giant billboard buses onto the premises, and also provides a curbside for them to load and unload passengers.

Clearly FlightCar doesn't burden an airport in the same way, however they do to some extent. Maybe if the airport worked with them and provided some portion of short term parking for their customers for a cut of the price it could be beneficial to both parties?

The degree of "burden" that FlightCar imposes on SFO is irrelevant to SFO's ability to charge a fee to FlightCar. SFO owns a platform and nobody is entitled to use it without paying, even if such use costs SFO nothing. (Which is not the case here, since FlightCar rentals are displacing car rentals that would otherwise pay a fee to SFO.)

Can you explain to me how SFO can prohibit FlightCar from picking up or dropping off passengers at SFO anymore than they can prohibit my friend from dropping me off or picking me up there? Since when you prohibit someone from the roads at a public facility when they're conforming to the law?

FlightCar is a business that uses another entity's property and services without permission and for profit,but without remuneration. This is not at all comparable to a private individual doing a friend a favor for free. I would imagine that the airport would start with a cease-and-desist letter, perhaps along with an offer to come to to some sort of revenue-sharing agreement for continued access. Failing a voluntary resolution, a lawsuit might follow.

To address your last point, let's use another example. Football stadiums are public facilities often owned by local municipalities. But that doesn't mean I can go in and start selling hot dogs.

But you can deliver hot dogs to stadium patrons on public roadways at the stadium. The airport can C&D all it wants. Fine. Cat and mouse. FlightCar will simply match the letter of the law. Good luck.

Disclaimer: I have had pizza delivered right up to Solider Field in Chicago before a game. Using a public road.

Are the roads inside an airport still public? I imagine they aren't, even the airport is publicly owned, the roads inside the airport complex fall under the airports jurisdiction in the same way a business compounds front gate marks the end of public road presence.

The roadways are almost certainly not public. Even if they were, the city could pass an ordinance making this completely illegal, just the same way that it's illegal to scalp a ticket within a certain range of the stadium. If the city/county's revenue stream is on the line you can be sure that it's in their best interest to do that.

Sure, but can the pizza guy come in and sell you pizza in the stadium, then take you off the property to collect?

I think the example would be more along the lines of the stadium wanting a fee from tailgaters cooking hot dogs in the parking lot.

Is SFO a public facility? It would not surprise me if the roads within the airport boundary were private roads.

If so, they can prohibit your friend from dropping you off just like any house owner can prohibit your friend from entering their driveway.

I definitely agree. SFO, or any airport for that matter, is not obligated to let companies like FlightCar do business on their premises. I was only trying to illustrate that there was a potential for them to capitalize on the situation. Given our litigious society, if they allowed FlightCar to operate they would probably just be sued in turn by the rental car agencies.

According to Wikipedia "SFO is owned by the City and County of San Francisco but located in adjacent San Mateo County". That should give them standing.