The switches are in dumb places. I never have an issue except when my one buddy rides. He must get in some odd way and he always turns it on. Might be the same case with you?
Yes, these switches were not put in the correct place for 2 reasons. First of all, when you want to turn on the heated seat, it's hard to see the switch. You have to feel for it and hope that you select the correct setting.
Secondly, it's in a spot that's very easy to hit by accident. When I first got the car, I hit that switch when I was trying to adjust the lumbar support. The switch for the lumbar support and heated seat are very close to together. My father once picked me up and when I got into the driver's seat, the seat was very hot. I noticed the heated seat was on. He must have hit it by accident when he adjusted the seat. You do get used to if over time, but it's definitely in a spot that's easy to hit by accident. They should have put these switches on the center console.
The only good thing is they do shut off automatically when you turn off the engine.