Probably because those seem to be the 'target' of those who would infringe upon the rights guaranteed by the Second Amendment to the Constitution of the United States of America.
It is my firm belief that if the gun manufacturers would start making them in various shades of green, i.e., spring green, forest green, leaf green, moss green, grass green, etc., these guns would be
far more readily accepted... even by folks like Hillary; heck, even by folks like Al Gore and his ilk who
embrace and
propound all things 'green'.... doncha think?
.