Water usage is probably my biggest. Living in a high desert, my wife and MIL see no problem with filling one side of the sink with hot soapy water to wash a few dishes because “that’s just how I’ve always done it”, to watering the grass and plants for hours. All of this makes me mental.
What does it mean to truly have free will?
Your brain is billions of electrically-reactive cells and interconnections, and your consciousness is electrical impulses shimmering around those cells in a more or less stable way.
A belief in free will implies the belief that you essentially have control over the physical mechanism that makes up you. A brain may not be a fully deterministic machine in the sense that a certain input condition may not always result in the same output, but it seems like a stretch to say that “you” both directly result from and directly control that mechanism.