I am terrible. But then I've professionally seen some terrible things. Even when I had uniformed police turn up I wanted to see warrant cards (courtesy of No 1 step daughter who didn't like being told off). I hate people who phone me and ask ME to confirm MY details. I tell them that "you called me, you jolly well confirm some details to me and if you can't you can put it in writing".
When I travel, I stash stuff in closed pockets rather than all in one bag so if the bag gets snatched I haven't lost everything. I write down number plates of suspicious cars; I won't leave the front windows open in I am in the back garden; I take my satnav, lead and window popper thing out of the car (and give the window a quick wipe).
I was brought up by a security conscious nutcase so I suspect some of it has rubbed off.