It’s a cost savings feature, but people don’t like it. It’s cheaper to make all the seats heated, and put those heated seats in the nonheated trims and give you the option to turn it on for the heated seat price.

For example if bmw made two seats, one non heated and one heated.

Bmw with no heated seats $45k Bmw with heated seats 48k.

Now if bmw only made one seat, and they saved money in production and sold the car like this,

Bmw with no heated seats 45k. But you have an option to buy the heated seat unlock, or pay a monthly sub. Bmw with heated seats, 48k.

The price is the same, but you get more options. But people hate this.