Darklen, i'm not sure why you are getting on TmSteyr's case, his question is legitimate... very in fact. If more people could answer that question, we'd have more quality games around.
TMSteyr, I don't know how much they were charging per person (i'd venture a 50$USD guess) but I'm pretty sure they had the help of a lot of 'veterans' or actual military personel. Since it was in a training facility and they were using real armor, i'd take a guess and say some of the airsofters are part of the military and 'made a few friendly calls' to organise this.
Just like Canada's Keystone Strike.... they have access to an helicopter. As an organiser, i've tried that a few times and having an helicopter for 2 hours costs near 1000$ on the civilian side. So, contacts is the key.
But i'm sure they did have a hell of a budget and some professional planners as well. Takes a lot of planning and guts to pull something like that off.
Although after watching the whole movie (dvd), i'm really not impressed by the quality of gaming. Their missions seems boring... They seem very keen on the 'peace-keeping' missions and less on the actual complexity of warfare. but that's my opinion.