Last in the series on unexpected selection behavior is Associative Hatch -- and it's probably not the kind of associative you're thinking of.
Typically, when we hear that a hatch is associative, we understand that to mean that when the boundary of the hatch is modified, the hatch will update to fill the new area. In the context of selection behaviors, though, it means that when the hatch is selected, its boundary is too.
Like the previous two settings, Associative Hatch is also on the Selection tab of the Options dialog. (It's also the PICKSTYLE variable.) The effects of checking this box are noticed most often in trying to delete a hatch. You select the hatch, press Delete, and suddenly the bounding object has been deleted too. If that's not what you wanted, all you need to do is undo, then hop into the Options dialog and put the setting back to normal.