Guy who actually have spme here
Its a "set it and forget it" fishing solution. >set some up>pitch tent, make camp. Etc.>collect fish for dinner
It either allows you to fish while doing other stuff, or increases your odds if you are actively fishing yourself
They do work, ive caught Perch and Rudd and I've never had to "rely" on them in any capacity, just setting them up for the sake of trying it out.
They automatically reel in on a bite, which sets the hook and "fights" the fish
They can be kinda scary though when you set them up and they accidentally trigger sending the hook flying towards you at mach 5
A novelty sure, but also a pretty cool tool imo
Heres a rough sketch of how I've set mine up before, people also ice fish with them and use them for catfish, also shooting decoys aparently