I've just read an excellent document aimed at teaching bubble placement to younglings (it is still draft, but it will be out there soon!)
One thing it says is with respect to decloaking ships: A cloaked ship can be caught in a stop or drag bubble, but it is likely that everybody camping the bubble will be completely unaware of the cloaked ship. The document states that you could litter the area between the bubble and camped celestial with corpses and cans to decloak any cloaked ship that gets within 2000m of any of your litter.
I seem to remember that littering like this was a bannable offence because an excess of objects on the grid can cause lag for the people just coming onto the grid, but I can not find that written down anywhere. Can anyone tell me if my memory is correct? And possibly provide a linky to the rule?