Yep! That person also lets their kids change seats while the car is in motion and complains about the warning beep. Arguably, if your backpack is heavy enough

Yep! That person also lets their kids change seats while the car is in motion and complains about the warning beep. Arguably, if your backpack is heavy enough to set off the sensor, it's probably a projectile hazard in itself and probably shouldn't be on the seat and instead in a foot well or in the cargo area.