I'm old enough to have not only seen this, but frequently done it myself! Very often there wasn't a 15A socket and a 2A was the only one available.I've seen pics of two bare wires (no earth) pushed in to a 15A round pin socket (still the standard in India)
A common variant was the electrical maypole, one or more two way adaptors with power devices run from cables from the centre of room light socket. Bayonet plug in adaptors for light sockets were sold for this purpose in those days, many UK rooms having no electrical sockets.
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