Without fratching about it, the way I see it is, it's someone else's property, if they don't want you parked there, you can't park there, and whatever rationalization you come up with doesn't matter, because you aren't the owner.
Some are strict, some don't care, but, in the end, if it ain't YOUR lot, you COULD be towed away... like speeding tickets, they can't catch everyone, but if they catch you, don't make things worse by being difficult.
My little catch phrase for such situations is, and always has been
"When you own the lot, then you can make the rules"
-They say nothing good happens at 3am, they're right, I happen at 3am....
-I'm an expert liar, but still a beginner at people believing them.