I don't see the appeal of heated seats, I've never turned the ones in my cars on. OK, I suppose when you've left your car in below zero weather it's useful.

Heated steering wheel on the other hand; that's heavenly.

I suppose if I ever find a BMW attractive enough to buy one despite this consumer-hating behavior (their grilles help me stay away), I'd figure out if I can unplug the seat from the control unit, and just plug it straight to a different power supply to get the heat. Or will they use something like HDMI's Digital Content Protection to prevent "heat piracy"?

Anyway it's all theoretical, it seems they've given up trying to pick your pocket for heated seats, but for other features they're still going to mug you: https://www.drive.com.au/news/bmw-admits-heated-seat-subscri...

You can buy the feature outright when you order the car.

This is just them figuring out that if they pre-install the HW in every car they get enough payments to cover the units never used.

It has two obvious consumer benefits: second hand sales (the new owner may really want it), and very occasional use.