I grew up on a farm in the Northwoods of Minnesota and everyone carried a knife. "Hand me your knife, would ya?" was the statement, not "Who's got a knife?" so I don't understand the concept of NOT carrying a knife. I've lost numerous knives to security and safety laws across the country because it's just second nature to have one in my pocket. (FYI, they don't let you take a SAK into the Capital building in DC.)
I use my knife every day for anything from opening packages, trimming loose threads, cleaning my nails, sharpening a pencil, stripping wires, scraping labels, cutting a sandwich, fixing a hose, trimming flashing, and numerous other minor tasks. It's a tool that is a part of who I am.
And don't forget whittling. You always need a knife so you have something to do with your hands while you're just sitting around. Yep, that's what we did before we had our smart phones to fiddle with.