The Grey, my guess on #3 is that he's trying to get data to verify or negate myths about gun ownership being a symptom of either being "privileged" (whatever the hell that means) or redneck simpletons. If that's the case, he probably also ought to have highest level of schooling completed. Sawin's answer regarding marital status might also be valid if "social status" is the new PC term.

Sawin's female?