Some so they can patrol neighborhoods and schools and malls, dreaming of someday stopping a massacre.
Some because it's easier to have something tangible to fear.
Some because they want the option to enact a massacre.
Some, observably, have made lucrative careers out of helping diseased minds select their targets.
Plausibly deniable, of course.
A desire for continuance of the existing order—and continuance of order is indeed a conservative urge.
The desired order includes gun massacres.
It's easily observed.