There's some truth to this, psychologically speaking . 99% of any scrutiny that we md'rs receive (in sketchy nice-manicured turf), is probably because WE OURSELVES display the persona of "... Oh no, does he see me..." skittishness. And when people passing by see that body language, they are prone to think "Gee, what's he doing, and gee is that allowed, or "gee, he might leave a hole", blah blah. When in fact, had it not been for your evasive behavior, they might not have given 2 sh#ts about you.
Example : When I was about 22-ish, there was a guy in our circle of friends, who was still only 19 or 20 (not 21 yrs. old yet, which is the age-at which you can enter bars, buy beer, etc... in CA). And the young fellow boasted to the rest of us : "I can get into any bar in town".
And since I knew he wasn't 21 yet (nor looked older than 21), I challenged him, and tried to call his bluff. But he persisted in his claim. So I told him "Oh, then you must have a fake ID, right ?" (that was a popular tactic with kids back when I was in high school). But he insisted that he didn't have a fake ID, and could get into any bar in town. I challenged him that the "bouncers will toss you out on your ear, and card you at the door, etc...". But he persisted in his claim that he's never carded, and goes into any bar he wants to.
When I realized he was serious, I took the bait and said "How do you do it then ?". His answer was simple : He walks right up to the bouncer at the door to the bar, shakes his hand, with a million dollar smile, and says "Hi, how ya doing ? !", and walks right in. He was never carded ! Because, you see, he'd figured out that the only people that the bouncers ever card, are people trying to avoid eye-contact, cutting a wide berth, acting evasive, etc..... But if you walk right up and shake their hand (act like you own the place), you're never carded !
MD'ing is the same way , for a lot of places : The ONLY reason we md'rs receive scrutiny, is that we're acting in an evasive manner. Locking eyes with any passing park worker, LEO car that passes by the street, locking eyes with anyone who stops to gawk, etc.... Then sure as sh*t, someone's gonna think "gee, what's that guy doing ?". It's as if we can be our own worst enemy, eh ?