One time while crawling under the crawlspace in the old house where we used to live I found about half a gallon of them all in a rusty pile on the ground. Luckily I was looking ahead of myself with the flashlight. I have no idea how they fell down, forgot to look, but a stud wall should have wood at the bottom, apparently in the 1890's they may have fudged a few things. You could make a metal or plastic container behind the drywall to catch them also. Currently I am putting them in empty plastic blade cases. I plan on buying a blade bank on my next order.
LOL about the fruit for neighborhood kids. I remember my parents checking fruit and baked goods for razor blades. They never found any!