I have carried a knife since my dad turned me loose with a small fixed blade on my fourth birthday, 65 years ago. I grew up in a rural area, working for farmers and my grandfather at various tasks. It was an essential tool to me. It could open feed sacks, clean fish and game, neuter pigs, clean your nails, peel an apple, and on and on.
I also come from a time and place where a boy who didn't have a knife on him was considered rather odd, where if a teacher asked for your knife it meant that he had left his at home and needed to cut something and you would get it back when he finished.
It is definitely not a romanticized thing, or macho, or to impress. It is to cut whatever needs cutting. It is also a lifelong habit, and a good one.