On fishing trips in Maine twice over the years had local people "checking us out" in a way that had senses tingling.
Once I was fishing downstream while a buddy was fishing upstream on a small stream. We were using radios (the little hand held FRS ones) to stay in contact- we would often do this to tell the other person how the stream was in the spot we were each fishing. Anyway I hear him on the radio but hes not really making sense. I can hear him talking and can tell hea talking to someone else. But I can tell from his responses something is weird. So I start heading back upstream to the road. I get to the last bend in the stream and can see a pickup on the bridge and the two guys looking out the passenger side toward my buddy. I keep "fishing" as I make my way upstream. I am turned purposely in a way that reveals a sidearm. Not threatening with it by any stretch (still holstered, strap down) but it was apparent it was there if one looked at me. The guy in the drivers seat happens to look around and sees me. Anyone acting in a "normal" way would have waved to me and said something like "any luck?". Instead he says to my friend "okay, good luck" (or something). His buddy seems put off by that and keeps talking to my friend. The driver again says something like "take care" or whatever. The passenger looks at him like "what?" And tries to keep talking. At this point driver slaps his buddy on the shoulder and jerks his head toward the downstreamside. Passenger looks out the window and sees me "fishing" and all I can guess is realized that having two people on either side of them is different than what they anticipated and then says something like "have a good trip" or whatever. They leave. I'm guessing they were casing my buddies pickup to see what they could steal. I doubt they would have robbed either of us but who knows. Unfortunately Maine has its share of tweakers.
The second one was also a Maine trip. I was there with five other guys and we had a great spot on a small pond. The access road to this site is a nasty little trail with mud about a half mile long that parallels the "main road" separated by about 100 yards of woods. But when you get to the campsite it's a beauty, right on the edge of a beautiful pond. Anyway the road in requires one go really slow and you can hear vehicles coming for quite a while before they leave the woods into the clearing of the sites (there are two campsites at this spot). It was early evening, we had just finished dinner and were just hanging around camp, one guy sitting at the fire, someone doing dishes etc. Also to note there are no other campsites within a good half hour or more of this spot.
Anyway we hear a vehicle coming but it's going really slow. Even slower than the road requires. This isnt odd by itself as lots of times people come into sites late (Lord knows we have plenty of times over the years). Just before the vehicle clears the woods it stops and sits there idling. Kind of weird. Some of us just sort of migrate away from the fire to different spots around the site, just kind of hanging out with one guy still sitting by the fire.
The truck idles into the clearing and stops. Two guys looking around. They ask how we're doing. The guy by the fire just says "good, how are you guys?". They mumble a response and then keep going to the next site where they turn around and leave. Nothing weird in and of itself except that it's late, they're miles from another campsite and they aren't stopping to set up camp at the other site. Okay, so fine, they leave. We hear the truck again going slowly down the access road. It gets to the main logging road and turn in a direction that is parallel to the nasty little access road. From our site we can hear the traffic on that main road when it's on the part near the site. We hear the truck slow down, then stop, which is weird as there is nothing at all on that main road. Next we hear someone walking through the woods toward the campsite. There is a sort of trail out to the road, but its not easy during the day let alone at night. And regardless, what is the person doing creeping back down to our site? So now we know something is up, so other than the guy by the fire we all go off into the woods in different places around the site and just stand there, but back where we are all in darkness. The guy gets to the far edge of the site but is still in the woods. He stands there for a while and then leaves and goes back to the main road. We hear a door shut anandthen the truck leaves. We all come back to the fire and just comment "well that was weird." Nothing else happened that trip and nothing was taken but it does make one wonder what they had planned. I'm guessing it was someone just looking to grab gear that was laying around. My Dad and his buddies had sleeping bags stolen one year in a similar sort of thing while they were fishing a stream. They heard the vehicle but were too far away to do anything. And when they got back to their truck the stuff was gone. There's some jerks out there unfortunately.