As much as we all want things like this, it isn't possible right now. I believe the way FOnline runs is it loads premade maps. In order to change any of the static objects on the map, the whole map must be reloaded, meaning anything on the ground disappears and maybe other such problems. Hopefully there will be a solution in the future, but AFAIK, we can't do it right now.
Things to decorate made me laugh, but a possiblity of buying things like Still, Workbench, plants etc. seem to be fine idea.
Devs already said they won't do that.
If you want to make enemies, try to change something.
Its really not as simple as dropping something on the ground and then it magically works, this is why when there was a bug and benches were spawning in peoples inventories they didnt work.
I don't think it's possible, people would drop such items in cities (I imagine some of them doing that just to block the path for other players) and someone would have to clean that mess.
They wouldn't block the hex, you can stand over them just like any item. Plus it wouldn't get messy because people stel everything. With unlimited shit that turns into items there should be shit everywhere but there isn't.