He doesn’t know that these porta’ potties aren’t hooked up to a sewage line to eliminate what Homer has done.
In the real world, behold a couple of the new Simpsons series two minifigs I have acquired mashed up with an portable toilet from a very odd City line kit. You can’t see it in this photo, but I love how the cylinder-like piece represents a roll of toilet paper. Can’t tell how many ply it is though.