Is interfering with the "go/no-go" decisionmaking of a flight crew a violation of 14 CFR 91.11?
If the airport received (US) federal funding, then it must be available for emergency or distress landings. The guard could require the people not camp, but forcing a flight to an aircraft without sufficient fuel, reserves, WX briefing, etc. is unprecedented. 

As a matter of practice, disoriented pilots who land at private and uncharted corporate airports in northern Canada are normally given fuel, food, and calls to get WX and file flight plans.

Perhaps someone better versed in Admiralty Law might comment.