You are correct that they can legally hunt and put up a tree stand. BUT OP is also legally 100% allowed to take that tree stand, as it’s on their property, hence why it’s considered polite and smart to ask permission to hunt property and put up stands

Edit; also, I don’t think “few people care about that”. I own a couple hundred acres, and care very much that people ask permission. Especially as we then tell them no tree stands with bolts or hardware into the tree and take them down off season, as we have and continue to harvest lumber off our land for hundreds of years, and nothing fucks the headsaw up like a tree stand spike.