If you make it known in advance that you make a particular charge then that's fine - but you cannot just impose an unreasonable charge after the event on a whim.
I agree, but if the pilot had bothered to call first to be told that landing fees are £75 then he could make the choice if he still wants to land. He didnt, so he should pay the fee!!! Simples.
What you're saying is that it's ok to land without PPR and then refuse the landing fee because you don't like how much it is?!!