I agree when I lived in Minnesota, but in Arizona you want the sun to set earlier so that the heat will start dropping in the evening. I think that is the main reason we don't participate, plus you want extra daylight in the morning when it isn't as hot to get things done.
Actually the reasoning for it being implemented was during WWII to move the daylight hours from the Morning to the Evening...
Otherwise without moving the clocks in the spring, it would be getting light at like 5 am in the east.
This allowed the rosie riverters to think it was not as late as it was and they would keep working until like 7 pm and not worry about going home in the dark.....