One of the items on the PDI list I have to go through on cars we sell is to check power outlet/cig lighter . There are lots that are live with the ignition off . Wasn't there supposed to have been something sorted about them being permanent live a few years ago ? IIRC it was after the newspapers went overboard about a couple of incidents involving children burning their fingers .
Which reminds me of a time when I was driving up the A1 with my lad . He kept passing sweets to me . I just kept accepting them and shoving them in my gob . Then he passed me the cig lighter .. OUCH

TBH I'm sure I've had cars in the past that had permanently live sockets in them, I had a Volvo V70 that had one in the boot because it came with a 12v cooler box plugged into it, a "gift" from the dealer that was probably added to the finance agreement - never used it once but the indicator light would stay on with the ignition switched off unless I unplugged it.

The Peugeot 307 SW (car from hell) that I had also had permanently live sockets in it because we spent 3 hours sitting on the dock of the bay in Roscoff waiting for a ferry one afternoon with the kids running the battery down watching videos in the seat-back thingys.