Marshalls obviously a Dick, & I'm pretty sure he'd change his tune if he had to stand up in court & defend that viewpoint, especially if it concerned subsequent abh/gbh/affray type charges, all of which can command hefty custodial sentences.
As for airsoft being a FULL CONTACT sport, is it fuck, take it to any sites insurers & ask them about liability coverage if the site organisers stated that, either verbally or via site pages etc, the insurers would likely withdraw any coverage on the spot.
I played real contact sports professionally, insurance became a necessity in order protect against cases in the event of serious injuries, for both civil & criminal proceedings.
If anybody connected to, or involved with any registered site & encourages or endorses physical contact beyond a pat on the shoulder, they'd be a dumb motherfucker.
@OP, certainly picked a suitable title for this thread, opened a big can of worms.
So, were you player one or player two ?