Unfortunately being an air show by its very nature it's very public - the planes are in the air for everyone to see for free for miles around. Last year the Vulcan flew over my workshop, very low and slow. I stood out and gawped and enjoyed it very much for those few minutes.
Does that make me a freeloader?
Ah....
If the Vulcan was going from A to B and it had to fly over your workshop, and you watched it, it is a chance and you are not a freeloader. The Vulcan is not in service so it is not tax-payers paying for it anymore, so if you want to donate to the
Vulcan in the Sky project, that is your choice, if you don't want to donate, that is your choice, and it still won't make you a freeloader if your taxes is not paying for it nor do you wish to donate to it. But the Vulcan had to go somewhere and it just happens to fly over you, it's just a chance.
If you live right at the edge of the airport or airbase, and end up seeing an airshow that is going on, right on your doorstep, every year, you are still not a freeloader, if you wish to donate, great, if you don't want to donate, don't worry, you are still not a freeloader. It just happens that you lived there, it can't be helped.
If you chose to go to buy a ticket and go into the airshow, you get to see the Vulcan close up, you get to see any other aircraft, sometimes you would be allowed to go into the cargo hold of a Hercules, sometimes you would be allowed in a cockpit, and you can ask pilots questions, as a tax-payer, you have the rights to see what you are paying for.
But...
In my option, an airshow is planned well in advance, and if you chose to go over to the airport or airfield and sit outside the fence, or go up the hills and watch it from there, it is not a chance, it is not a luck that the Vulcan flew over you, you knew those planes would fly around, so you chose to go and watch it for free. The people inside the airbase who paid for their tickets are not really just paying to get a closer view of the aircraft or to get front seats or to chat to a pilot, some parts of the cost of the tickets had to go towards fuel for the aircraft (not every aircraft will be public and paid by taxes as most of them will be private such as the Vulcan), some parts of the ticket have to go to so and so.
It is no different from say, the fans pay tickets to watch a football match, part of the sales of the tickets goes to the club, and to pay the football players, so the fans are paying for it, but you chose to stay outside the grounds, and climb up a tall tree, and sit on the top of the tree, and get to watch a football match without paying.
Okay, maybe not freeloader, but airshows would not happen if it wasn't for people who paid the tickets to watch, without them paying for the tickets, there would be no airshow, so you could not have watched aircraft for free, but they did pay the tickets, aircraft get flow, and you watched for free. See? For you to not have watched the aircraft for free, the aircraft would not be flying, and if they're not flying, most of the public would not be paying tickets. They pay, aircraft flies, you watch. They don't pay, aircraft don't fly, you got nothing to watch.