That was done at a time when people freely used their SS# for ID purposes,,even though it says 'Not for Identification Purposes' on the card.
There wasn't any NCIC file to drop a SS# into to retrieve a name anyway, so having someones firearm, golf clubs or sterio with a SS# did nothing to help find the owner when recovered.
People loved it though. Those handy little electric scriber tools got a good workout and everyone felt safe and protected.
Brought to you by the same people that did things like used individuals SS# as their State Sales Tax license number for self owned business.
'Post in a Conspicuous Location' it said....Ummmm,,maybe not.
That's since been changed, but not all that long ago.
