Yeah, I sometimes do those things as well. I'm probably similr to you, as I've got big issues with derealization as well.
I think I just end up staring at something as a means to let my mind wander - but I'm (apparently) not crazy.
The only means I can think to get rid of it, if you really want to, would be to consciously interrupt your thought pattern when you start staring at something. To say, for instance "I don't need to stare at that banana, I'll look elsewhere"