It is bannable but you have to record the person placing it or it's no good, just make it breakable so we don't need to worry about bans. There shouldn't be unbreakable items that are able to be obtained by players in the first place.
Well you know how when you break an enderchest and get obsidian? You are not allowed to place obsidian. It could become like that.
Yea, but as Sando said going under the map to break the bed was always helpful. Besides trolling really never happened anyways when wool was breakable.