The issue is you already paid for the heating element in the seats when you bought the car Not necessarily - it's possible the cost of that item in the BOM is

The issue is you already paid for the heating element in the seats when you bought the car Not necessarily - it's possible the cost of that item in the BOM is separated and offset only against the expected revenue from those paying specifically to have it. Anyway, here's how I'd split this baby: BMW can charge to enable the heated seats in whatever way they want, but the consumer is also allowed to modchip their car to enable the heated seats without paying if they want.