That explanation actually does make sense...if you ransack an office and make it look like a meth addict was looking for valuables to pawn, they're less likely to find the bug you hid above the ceiling grid.

That having been said, I'm not the expert here. Has there ever been an actual case of someone planting a bomb anywhere, rigging the break-in to look like a drug-crazed thug?

At some point, if we act too paranoid, the terrorists won't even need bombs to cause terror. It's been noted before that a dozen or so operatives could, in a coordinated "attack", do things at various major airports to cause terminal dumps, gumming up travel worldwide.

I've wondered before even if evacuation and searching are the appropriate response to bomb threats, which are, without fail, attempts to get out of work/school early, get out of an exam, or screw with someone you don't like. When I worked at a high school, I was told to never answer a ringing pay phone: students would call in bomb threats to the lobby pay phones, and if an employee answered the call, they would have no choice but to report the incident to the principal and have the school evacuated.