When I build them as I've described, I have no problems with wood movement.
This approach eliminates issue with the side of the case and other factors which cause a tight drawer. The drawer also pulls out beautifully as the front exit is precisely fitted to the front and back of the drawer, so the drawer does not get loose as it is pulled out of the register.
Typically I plane the sides hollow as I'm preparing stock and if they have a slight bow to them I will put the bow toward the inside so that they will have a tendency to stay that way or to straighten, rather than bow outward.
I have made drawers by fitting and they're a headache. Once they're fitted they're too loose for my taste, and if they move and require more fitting then I need to travel to a place, work on the floor then refinish, no thanks.