(AFAIK, face to face sale is legal, which does apply in the street. Say if I pulled up in my car, and you pulled up in yours, and money and gun changed hands)
BLUF: The private party buyers were never told that a legal action was not welcome by the property owner(s), and to please leave. The situation was immediately escalated by the cops. You do not (in civilian world) get to escalate without reason a situation that is legal to begin with.
So if I see someone with a gun I like, I can't offer them money for it?
I've done it before, yes at gun shows, but if I saw someone I knew was thinking of selling, I'd at least ask what they were interested in getting. Kind of like the cash for clunkers, except in that program, the g'mnt was offering more than the market, here it is the other way around.
I've had people offer to buy my bikes when I go to the store. Am I likely to sell? I may for the right price, at the right time.
Are you saying they (the private buyers) should have asked the church permission first? I've met people in places like church parking lots when looking at used bikes. Do I need to ask permission first? Seems to me like: "The owners of the property do not want this going on." would be all that is needed.
Hell, I've taken naps in oddball parking lots when on long trips without trying to find the property owner.
