Well some folks no doubt buy cheap knives so they can afford expensive guns........
Among my "stuff" is what several kids thought was a "messed up arrow head"....even though the size alone would have made anyone round abouts that "knew anything" know it was a "messed up Atl-atl dart war head" and they would have been wrong as well. It was someone's knife likely just before old Pounce (come on , pronounce it Pouncy!) de Leon brought the wonders of moderninity and tourism to Florida. Folks that live in places where man meets nature NEED a knife, folks that work someplace other than the sterile halls of metropolis NEED a knife.
Up through about 9th grade there was technecally a knife ban in public schools, though not only did it not get enforced but it was not unusual for a male teacher especially to ask to borrow your knife or even just see it. When intergration happened in my school system, suddenly the knife ban rules were enforced. Still a lot of us still carried. I had a pearlish handled Old Grand Dad my Old Grand Dad gave me I continued to carry on regular school days until Same Grand Dad gave me my Demo Kit Knife which I then carried. One of my best white buddies carried a hawk billed Barlow with the long bolster (as did my Mother BTW) and one of my best Black Buddies carried a thin, long folding "fruit knife"......that he actually used for a fruit knife. Actually knew a kid that carried a straight razor and noticed the occasional single edge razor wedged between the heel and sole of a shoe while folks changed in gym class. Basically very few of the teachers "looked for a knife" and having a knife was generally just an adittional "charge" if one got into trouble. Oddly although there were a few pretty bad, as in hospital bad, fights I don't recall anyone during a normal school day getting carved up or stabbed.....with a knife..... #2 pencil or ball point pen or fork from lunchroom yes, but no knives. Football games and dances maybe a few times in three years, but rare and oddly not between races.
When I went into the service the first time in the early 1970's I was SHOCKED that first night when they told us they were checking every thing we had for weapons and that included common folding pocket knives that would all be confiscated. Induction center had not warned us either. I had one of my best friends in my pocket and he was a tool by gosh! It was my demo kit knife (don't start, that is what we called them in Demo School and one was part of the Infantry Platoon demo kit and a part that had to be often replaced) I had taken to carrying, non military types can think "Scout Knife, one blade, can opener, bottle opener/flat head screwdriver, marlin spike/punch, bail hanger all stainless no scales. Mine was one of the older models with the stud on the Screwdriver/ bottle opener that helped open it and push out the clip guide pin on an M-1 Garand. I palmed my knife and when a Smokey The Bear hatted NCO came to check my gear opened my palm so he could see it, looked him in the eye, and pocketed it. He sort of smiled and nodded and went on his way. Did not even raise an eyebrow at the little sharpening stone in my shaving kit either. For the next ten days or so I had apparently the only knife in the training platoon. First time they let us go to the little PX annex for polish, soap, and brasso a lot of Barlow knives got bought and a few more expensive Old Henrys and Trees got bought as well. I resharpened and cleaned up a lot edges on knives those first eight weeks. I still have at least one of the Demo kit knives I occasionally carry, though that original one disappeared from the top of my foot locker while I sat next to it cleaning my boots moments before lights out about 14 weeks later. Never knew it had legs. Well at least another Infantryman got it....
Yes the slim little sheath knife I wear to church along the inside seam of my trousers might be worth more than my (cheap) EDC gun. My day to day carry knife though is the cheap knife from Home depot that RC raved about not long before he left us and IIRC cost about $10 and it has worked fine. I even, after using it a bit, bought one for each of my kids for camping and such.
-kBob
Since then I make sure to do a quick pat to insure that the basics are in place. 
