This is a neat thread, it really made me pause and think about it some. Up until the last year or so, I used a knife very frequently during the day as my work usually facilitated knife use quite handily. Being a communications technician in the past, I used a knife for everything from stripping and splicing coax and fiber cables to opening packaging of various sorts and even preparing food now and then.
Now in my newfound vocation as a software engineer, I sit at a desk... Not the most conducive outlet for knife use. However, I have gravitated towards knives that provide a sense of tactile pleasure as I will often use a knife as a bit of a worry stone as I am puzzling over bits of code here and there. My lambsfoot knives in particular suit this role admirably (that swayback is an ergonomic marvel) as do some of my other wood clad wonders.
So that coupled with the fact that, like many of you, I find uses for my knives even when I could get away with not. I make a point to use my knives for food prep, even when there are kitchen knives on hand. I just enjoy using them and I enjoy having them available to me because I know that the moment I decide to leave them at home or in my office, I will certainly find that I miss them and could REALLY use one!