hitting the fan
During the early development of the American M-1 tank, it was said that the fancy aiming assistance had locked onto the spinning exhaust fan of a lavatory, and that the main gun had permanently removed the fan, and I guess the room, as a threat. A lot of the bugs have been worked out of the M-1's electronics systems since then, but if you have to engage a lavatory, portable or not, it's probably a good weapon to use.
Airline toilets do inflict ground damage now and then, generally with "blue ice"--leaked liquids that have frozen into a lump at altitude, and which come loose when the airplane descends into warmer air before landing. Years ago, a house near the Denver airport suffered a blue ice impact, which holed a roof and a table.