I guess the reason customs dont do it are the same reasons people walking through customs dont do it.....
If you werent there on the day, or have never been to indy on the gold coast you will not understand one of the main reasons a lot of spectators go.
The ARMY boys were as stated earlier "blowing off steam" and playing along with the majority...
BTW if it were my company chopper with sponsorship or my company name on it, think of all the free advertising i would have got....it would be priceless.