~Mopeds have fully automatic transmission and hand controls, if you don't have the full use of both legs, you can still ride a moped.
~It's actually easier to fight from a moped than a motorcycle, since you really only need one hand to operate it, especially if you have put the rear brake and throttle both on the same side.
With a length of chain in the other hand, it ensures you can give a lesson to the jerk who just threw a brick at you with speed and efficiency.
~If you are unsatisfied with the job you've done in parking it, you can just pick the damn thing up and PUT it where you want - I'd like to see you do that with a 250cc Motorcycle.
~Most moped repairs can be done with a toolbox small enough to fix in one's saddlebags and can be accomplished in mere minutes, up to and including patching a flat.
~It is possible to fire a paintball gun accurately from a moped - nothing more humiliating to brick throwers or obnoxious auto owners than a couple of nice, big, PINK, ultra-neon dayglo splats on them or thier vehicle.
~Again, the simplicity of repair, you can dismount the entire engine and transmission assembly with (usually) three bolts, a cable and, two electrical connections, and just carry the whole damn thing into your workshop.