It isn't murder to get away; you don't seem to want to listen to people who are telling you otherwise. Maybe you have just got it wrong on the occasions you have been? I have been twice and never had a problem.
The only time we had a problem was the first time we went (for the friendly last year)and parked on the main car park. After that we have parked either on Barton Aerodrome or got there early and parked on the exit road.