.... (Indian Artifact) and the Officials had no mercy. Is that typical (having no mercy) on people with metal detectors? ...
No. They are thankfully Totally different leagues. The indian stuff (bones especially) are super hyped of protection.
Humorously for example, one time we got stopped in Las Padres National forest. The fellows who pulled us over (for having parked in an awkward spot in the middle of nowhere) were grilling us on what we were doing. They had suspected game poachers or illegal pot growers, so they'd been staking out our vehicle. But when they saw our detectors, and that we had no hunting rifles, and our licenses checked out squeeky clean, they were sort of confused as to what to do next. Their suspicions had evaporated.
So they began to question the detectors. One of them said "You're not disturbing Indian artifacts, are you ?". To which we could truthfully answer "no" (since the Indians here had no refined metals). They shrugged their shoulders and let us go on our way.
And this is not unique. I've heard of guys getting the riot act read-to-them for disturbing arrowheads, mortars, pestles, beads, bones, feathers, etc.... Yet in the exact same zones, md'rs are ignored.
Is that to say that if you asked enough purist archies that you might not find one to object ? No, of course you can ALWAYS find someone in this world who "doesn't like it". But technically, you're not in violation of ARPA if you're hunting modern stuff, or nuggets, or meteorites, or the ring your wife lost last week. But Indian stuff, on the other hand, is in a different league.
And to whatever extent you *could* find some horror story of someone "roughed up " for md'ing, it's invariably someone night sneaking obvious sensitive spots/monuments. Or someone being obstinate who can't take a warning. Or someone with no common sense and parades himself around during an archie convention, etc.....