Only cop cars had all locks in the car keyed off the ignition key. Standard production cars were as Larry stated above.
If you are buying a new ignition switch and tumbler lock I would replace all of the locks at the same time (you have no idea how many old keys for your car are still floating around out in the world). A former owner might take a fancy to your car after it is all restored and just drive off with it (he can always hot wire the car like you are doing now to by-pass the ignition lock if he still has a door key).
When I buy a used car I generally replace all of the locks with new ones keyed off the ignition switch because I dislike having to carry two keys per car (when you have seven vehicles licensed and insured at a time they begin to dig a hole in your pocket (especially the new cars and trucks with key fobs to unlock the doors and reset the theft alarms).