I imagine the duct tape also catches any stray burrs that may break off as well

.
What I can’t imagine is how anyone would prefer to have a duct tape or cheap cordura sheath over leather or good kydex.
I got him beat.
About forty years ago when I lived in one town and worked in another; no car yet, I often slept / camped in the building / business I worked in.
Some times I house sat for friends in that town.
This was until I found a place.
This ment food prep in primitive surroundings.
I bought a Henckels Classic 4in paring knife and made a "sheath" so I could carry the knife in my back pack.
. . . . using dense heavy cardboard like from the back of an old paper tablet.
I folded it around the edge and STAPLED the open side.
Even after I had put down roots in a nice home I carried that "EDC" for years.
Concealed, half inch over legal, I never gave it a thought. Yes SD was another reason. Not quick draw but at least it was with me.
For something to do, back then, in my spare time I hand sanded the grind lines off using wet or dry and a rubber block working through all the grits until it was mirror polished (and inadvertently a bit thinner). She's a bad a$$ little slicer !
Still have the knife, stays in the kitchen now.
Still have the alleged sheath in a drawer . . . cause you never know when you might need to go on walk about.