On the topic of use of scanners and, particularly, transceivers, I'm with HD all the way. Having had someone messing around with a transmitter on the frequency that I'm controlling on, I'm hoping not to ever repeat the experience.
As to airport extension fees, it's just the way the world works. Airports, certainly in the UK, are businesses and in this respect they use charges to influence cutomer behaviour. The extension fee bears little relationship to the costs of keeping the airport open (normally needs ATC staff - controllers, engineers, support people - fire cover - lots for a big aircraft - security - required by DfT etc. all on some sort of overtime dyty) but is intended to deter casual demands for extensions whilst still providing a service to airport customers.
I mean no disrespect to the general aviation community but the customers that an airport values are those that operate commercial aeroplanes. A commercial aircraft operator, particularly one that is establishing a new base or that drives a hard bargain, probably pays little in landing fees but buys as much fuel as the local club does in a month, the passengers generate money for the airport in the shops, cafes, restaurants and car parks. It's just business I'm afraid - and basic economics.