I use them a lot here in Michigan. When I head out west to hunt, I always bring several to put out. I usually lock them to a tree but anyone could steal them if they were determined enough. Haven’t lost one yet. I did have some dirty hippies in Colorado on one of my cameras. They were using the stream as a bathroom.
Many "dry ground" lion hunters here in the Southwest use cell phone cameras, get the pictures of a cat then load up the dogs and go catch them. Total BS and unethical in my opinion.
I have a few cameras out, but only check them once every 4 months or so. It is a long drive and 15 miles roundtrip on foot or mules to check them. It is neat to see what is on them, but they are not really too useful for hunting.
I wouldn’t say you need them. Just another tool. Gives me an idea of what’s in the area and the confidence to keep hunting if I’m not seeing animals knowing what is likely still in the area. I carry a couple climbing sticks and hang them in a tree about 12’ up to deter thieves.
Use mine as much as possible. I love to see how the different animals interact in nature and just see the things you wouldnt typically see while out in the woods.
Equating that to "high fence" hunting or considering it cheating seems pretty asinine to me. Probably just can't figure out how to use one themselves.