Well, there are at least 10 sceneries sold every week for msfs alone that include some form of logo etc. Not sure but the flightsim scene would have to stop developing if everything needs some kind of permission. Where is the beginning, where the end? The airport building itself could be seen as some form of artwork from architect xyc.
Im not sure how many developers, lets say of EDDM, asked SIXT and Lufthansa for permission for the big advertising. Or the developer of a RKSI asked ASIANA, Korea Air or whatever logos are on the terminal buildings.
Or GSX dev asking every single company of the world from the ground vehicles if he can use the logos and fonts. I just cant believe that... Or the gates. So many different logos of banks all over the world, or car rent companies and whatnot.
But sure, im not the one who is trying to get you into trouble. I have asked the owners for the airfield i do and everyone was fine. But thats small local companies, cant be compared.
Besides that, im not so sure if some of those companies would even differentiate between payware and freeware.... basically your spreading other ppls work. So we all have to stop doing what we do if everything is that harsh in the flightsim world.
Also those companies often pay the airport to be on there, so they would have to pay us if we make advertising for them...
Just to be sure, that is only what i think, has no legal meaning in any way. I know it can be weird, i work in the web-dev sector..... and seen most things. THis is just what i see on the hundres of airports i own. I doubt they all asked for logos. Maybe they have of course, i dont know.