Old houses with razor blade slots

Customers like the appearance, ease of use, safety, size and storage space of the razor blade cartridge They mention that it looks nice in the medicine cabinet

In the old days, there was a slot in the medicine cabinet to drop the used razors behind the wall Mine still has it and I am sure there are

razor shark slot 112 Miniature Retro Medicine Cabinet Items - band aids, aspirin

razor shark slot free so where do all those used razor blades go? in the bottom of the wall! and they wait there until some poor future remodeler decides to