If I felt unsafe enough to consider buying an AK for protection, I'd take that AK money and use it for a down payment on a house in a safer neighborhood.
I don't really care that people buy arsenals and ammo, but using fear of government as justification seems dishonest. Just say you want one because it makes you feel powerful, or that you like to shoot shlt. As a hobby - sure, but using fear to justify your hobby is disingenuous at best.
If you ever want to see what I mean by the arbitrariness of categories, check the situation of polarized politics. The next time a Martian visits earth, try to explain to him to why those who favor allowing capital punishment also oppose the elimination of a fetus in the mother's womb.