I’m guessing that for the most part, the people who have pictures taken with guns aren’t those who actually own and use them. It would be as pointless as me taking pictures with my hammers.
Craftsmen are often pictured with their tools.
I try to include a gun or knife or other implement in most personal photographs. When I digitized my parents lifetime of family photographs, it became apparent that including an implement made the photos much more valuable and interesting. The least valuable were landscapes. They were pretty meaningless without a person and implements to give them context.
Vehicles work pretty well as implements. They are interesting for context and help date the picture, though with digital photography, date/time stamps are usually included and are extremely valuable.