Gee, there are a lot of misconceptions about air conditioners in cars!
First, the air conditioner compressor has a clutch, which is electronicslly controlled. When the air conditioner does not need cooling of the air, the clutch is released so there is no engine drag - it is not "on all the time." This is to improve average gas mileage by minimizing load. Turning on the automatic climate control does not automatically engage the compressor unless cooling is needed.
The auto air conditioner IS an automatic climate control system. There is a temperature that you set, and the system will put out heat or coolness to make the inside of the car match that temperature. Unlike a lot of premium vehicles, there is only one "zone" but there are two sensors for car interior temperature.
Turning the system off in my car is very easy. Just hit the fan speed lower button until the temp light goes off and the system is shut down. Takes a second.
I think the auto system looks better, takes less time away from your driving attention, and is easier to run the defroster feature. As part of the premium package, it is not all that expensive to add it in the U.S.
If you are in a hot climate, I think that the auto system probably makes life easier - just set it and forget it.