As a health care provider, I don't generally don't think to ask people about firearms. It can be relevant, but not for what brings most people to the doctor. But, whenever someone is showing signs of suicidal or violent tendencies, that's when these kind of questions pop up; it's just something that has to be done in these kind of cases. And of course, whenever soon-to-be parents are fretting of what to do, some friendly advise on gun safety is always good.
Then again, I'm not exactly anti-gun... If patients want to talk guns, I could keep them there all day! Otherwise its back to boring small talk with most of them.
As for me, the last provider I saw was someone I shoot clays with now and again. Most of that visit was discussing where to find a left-handed shotgun for him.
“There are three reasons to own a gun. To protect yourself and your family, to hunt dangerous and delicious animals, and to keep the King of England out of your face.” - Krusty the Clown