Why? Lots of cars have remote starters, they just gotta hit that and the car is now running with the AC going and the doors locked (assuming they'll actually be back in a few minutes since most of those auto shut off after 5-10 minutes)
Could also just disconnect the remote with the key (assuming they aren't ones that are attached) and start it and take the remote with you to lock/unlock it.
Could also just disconnect the remote with the key (assuming they aren't ones that are attached) and start it and take the remote with you to lock/unlock it.