Some nonsense being thrown about here. The Typhoon pilot didn't "teach a lesson" - that would be to completely misunderstand the nature of flying. He was simply landing his aeroplane. Sometimes the approach is higher, sometimes lower, either way it is completely routine and safe.
Out of the many, many thousands of landings made at Waddington, I seem to recall that only a couple could be described as dangerous, so that's not a bad record. A Starfighter did clip the fence once, but even that didn't result in any casualties.
In reality, the chances of being hit by an aircraft landing at Waddington are virtually zero, therefore one can claim that there is no risk. Obviously it's not impossible but nothing is. Rather like the Typhoon and F-16 landing, they look rather more spectacular than they really are. The real issue is when stupid people stand on ladders directly on the approach line and are therefore unable to make a hasty retreat. Likewise, one could argue that some people aren't clued-up enough to judge if a landing is about to end in disaster (and move away quickly), so maybe they should stand in a place where there is absolutely no risk - even a small one.
As for freeloading, that isn't the reason why most (not all) people stand on the A15. The main motive is to obtain good photographs. The display line and position of the sun means that the only really good images of the aircraft have to be taken from the road, where one can get closer to the aircraft. I've done it many times myself. I wouldn't pay to stand half a mile away from an aircraft when I can get up close outside the airfield for free. That would be crazy.
Incidentally, I seem to recall that the F-16 landing was on the Wednesday when it arrived (after flying a validation/practice display). And yes, people were on the road but P&V wasn't open on the Wednesday. As one poster has said, many people do pay to park in the P&V and then walk outside to stand on the road - to get the best photos.