In the few weeks I've been here I've run into a few rhetorical questions about why we can still get the open-front plugs in hardware stores.
I remember when I was a kid (back in the 1980s/early 90s), such plugs were still being sold with the easily-lost cardboard insulators to cover the screws. On 30 or 40 year old appliances that hadn't been unplugged in ages, the cardboard would sometimes crumble away the moment you touched it.
The ones I've bought in the last three or four years [Eagle now makes them in Mexico :-( ] have been "improved."
The insulating disk is now a piece of gray plastic that seems to fit tighter against the plug pins and doesn't seem prone to easily get lost. To work them off you have to pick at them with your fingernail for a little bit till they work off slightly. I've even replaced the cardboard disks with extra plastic ones from the hardware stores on some plugs already installed at home.
I don't think Leviton makes open-front plugs anymore - everything is dead-front now.. I still run into new-old-stock open front Leviton flat-handle Bakelite plugs in little hardware stores every so often.
My pet peeve is why does Eagle still make some plugs with GALVANIZED IRON or steel pins (prone to rust) instead of brass or copper pins (which makes for better conductor also).