It makes it more concealable and easier to swing around in close quarters.
It does make it easier to conceal and shorter M4 style rifles come in SBR form for low visibility close range style engagement.
Dummy was protesting and was ignorant of a law. Most of us are ignorant to many laws.
If the system wants to prosecute then she has no excuse or defense. “Ignorance is no excuse.” (Video proof of) So it then becomes a discussion of leniency, or whos lawyer can spin the best yarn.