Maybe, but the other 2 weren't cut and the tiedowns that were they left 2 ft or so of cord and the anchors in the ground. I would have thought they would have picked all that up. I do believe they sell that stuff at the end of the year too? Not sure. lesson learned and i guess i will have back up placards sent with in the event this ever happens again.
Is it legal? yes Should it be? No.
How about permanent ice houses on public lakes. By your logic I should be able to drill holes right up next to their houses and the buffer zone rule should be abolished.
You are correct
You can legally sit in any blind or stand left on public land. Years back we were hunting a sandbar South of Washburn and we had dug in a couple blinds we had made out of hog panels and burlap to sit in when goose hunting. One morning we showed up to hunt only to find the local game warden hunting out of our blinds, all we could do was move to another sandbar.
Everyone has one 
And you handled it correctly. 99.9% of others wouldn't.
I couldn't care less if they banned leaving shacks unattended. Guys hold spots all winter doing that. But fishing is a bit different. You can put 15 different guys in a good ice fishing spot and someone's going to have luck, maybe even all of them. Put 15 guys all bowhunting in the same small section of public land and no ones doing well.
I see no difference I guess, mammals move around no different than fish. I've hunted a really small chunk of woods with 3 other buddies at the same time on multiple occasions, looking back it was comical how we "surrounded" things. Every time we did this at least 2 of us seen deer and had shots most likely if we wanted. I've been ice fishing and hammering perch, crappie or gills in one spot but have a buddy drill a hole 10ft over and can barely catch a thing. There is such a thing as spot on the spot for fishing sometimes so if you are ok with an ice shack saving "their spot" on public water then I still don't see the difference.
