Why do people always assume they have to have permission to detect somewhere that isn't private property?
As someone who started in the 1970s, before there was internet, before there was FMDAC: The only communication with the outside world anyone had (outside of their own city's know-how) was the magazines, at best. So having come from "those days", I'll take a crack at your question:
Back in the early days, you're right: this type question of "
can I detect a park?" or "
can I detect such & such beach?" etc... would never have crossed anyone's mind. I mean, if someone had posed such a question, we'd have probably have wondered "why not?". In other words, the we'd have never have suspected YOU COULDN'T , and wouldn't understand why anyone would wonder. Sure: we had the presence-of-mind not to go waltzing over beach-blankets, or go during school hours, or be in the middle-of-deep retrievals when busy-bodies are watching. And I recall that we also had the presence of mind to avoid obvious historic sensitive monuments. But beyond that, we never fretted about run-of-the-mill parks, beaches and schools.
So when did this fear start, where people run into city halls all over, and/or post questions wondering "if they can" ?
The first I saw of this mind-set, was in the early days of the FMDAC in the mid 1980s. For the very first time, stories began to circulate about "bootings" and "laws" and other such legal things. Each edition of the FMDAC periodical would always contain several such stories, to understandably garner solidarity amongst the clubs. About the same time, stories in the magazines also chronicled various legal things. "Codes of ethics" began to appear in the magazines, and with each detector purchase. One point of which always says something to the effect of:
"I will know and obey all laws". At first glance, this is all a noble thing to do, to "spread the word" and "gain solidarity", and "obey laws" right? But I noticed an odd side-effect began to happen:
As people read of such far-away places where a rule was invented, or a person was in hot-water, then they might begin to ask themselves:
"Gee, I wonder if there's laws where I'm at, or where I'm about to travel to?" So what's the knee-jerk reaction of such people reading the scary stories? TO GO ASK! (sounds reasonable enough, afterall, you "can't be too safe"). But then the snow-ball starts: a lot of these people going and asking, might get "no's", in places that, quite frankly, never had a problem before. Some desk-bound bureaucrat would morph something else to apply (disturbance clauses, or cultural heritage, etc...). So what does that md'r do? Spreads the info to others. Sounds reasonable enough right? Afterall, you wouldn't want your friends to get in trouble right? Even an entire book was made on this principle: "Treasure laws of the United States", detailing a state-by-state state parks rules. How did the author get his info? HE ASKED. Yup, sent out 50 xeroxed letters to each of the 50 states, and simply put the answers in this book in alphabetic order. Sounds logical enough. This just leads to more asking, as you can imagine, or seeking clarifications, thus now more "pressing questions" on bureauucrat's desks, thus more "no's", thus leading to more asking... See the vicious circle?
That's my theory anyhow. People will often answer the question you pose by saying "holes" or because of archies, etc... But if you trace it back further than that (how did "holes" come on someone's radar, or how did md'ing get on archie's radars?) you arrive back at the phenomenom I speak of: md'rs going and making themselves a bid red "x" in need of attention and someone else's princely say-so.