I have seen them jammed. Replaced with straight wire, etc. Also where I live has houses that predate electricity - in my area of the northeast US, for instanc

I have seen them jammed. Replaced with straight wire, etc. Also where I live has houses that predate electricity - in my area of the northeast US, for instance. So some of the wiring is, most definitely, old. Heck, some old fuse systems have been known to be the perfect size for coins. ;)