Can you explain how it's possible for the side bolster to physically contact the seat controls? Because the seat controls are protected by a rigid molded piece and the upholstered bolster is not physically large enough to reach the seat controls.
I do have one possible explanation for phantom seat movement. I recently injured my back skiing (yes, even now there is enough snow in the mountains to ski). For a few weeks I had extremely limited mobility. The first time I figured I had healed enough to drive myself somewhere I noticed the seat moving as I exited. Turns out I was putting my palm on the side bolster by my thigh to help support my upper body weight as I prepared to stand. And my fingers were activating the electric seat controls. Maybe this explains some of the "phantom" seat movements?
After looking at it more closely, It must have been my leg touching the controls. Maybe the pressure from the bolster on the back of my thigh masks the feeling of my leg touching the controls.... Either way, I'm pretty confident that my seats do not move on their own, I think it's dragging parts of my body across the controls as I get out