Mine are bolted to the wall studs and slab.
Few years back someone on the Silencer Talk forum came home to his front door busted and his 600+ pound safe gone.
The most important things in his safe was a sub machine gun, several SBR's and suppressors.
He said it had to have been someone he knew or someone that saw him shooting his cool stuff at the range and followed him home.
I am always amazed when I see posts on Facebook or other social media sites where people show off guns they own, including some truly rare or collectible stuff.
Also...most of us have at least somebody in our circle of family members and/or friends who isn't exactly an honest, upstanding citizen. You have to be very circumspect when talking with anyone about your guns...