AIRSMILES
Your first sentence sums up the whole problem.Most airfields recognize an area where most spotters congregate,and seem to accept the situation.There are a couple of major airports in the U.K where they appear to not tolerate spotters at all,altho'one has a "visitors centre" which will be usless when the planted trees reach maturity(why did the tree planting stop just as it reached the edge of a certain well known hotel who advertize views over the airfield).With the cost as the consistant policing,would it not be possibly as cheap to designate an area where the majority would gather,and then concentrate on the 'loose cannons'who decide they know better(and yes i accept there are some).