This is a fuse box, with a flathead you should be able to open it and/or pull a small tray with the fuse itself inside. You Brits do your electrical wiring with ring-shaped circuits and put a fuse in every outlet.
This kind of outlet is intended for things you don’t unplug and a socket doesn’t make sense, usually boilers, ovens, stoves, ACs, alarm systems as already commented…
Don’t be fooled, taxes are just a way to extract the fruit of the poor folks’ labor and give it to the rich and powerful. Always have been, since their inception. Not just in America, here in the (highly idealized by lemmy) EU I cost my company 3200€ a month, 1850€ go to my bank account and 1350€ to the government, plus up to a 21% vat from the things I purchase. Amazon pays literally 0€ in taxes.