What the title says. Regardless of which table you choose and save your map with, it always ends up with the green multiplayer one.
That's because you play custom adventures from the MP lobby. Not really a bug, though I would like to be able to use the wooden table in custom games.
Oh, so unlike every other layer, the table is just dependent on where you're playing and is purely for show in the editor. Seems like the table layer should be removed from the editor for consistency in that case (I mean, why would you ever want to hide the table anyway). Surely not a bug, though. Thanks for clearing up the confusion, @Kalin.