This is not something to worry about - there are many reasons that your dog is not a licker - and believe me, it is much easier dealing with a none licker!

If you have a deep need for your dog to lick then it is a behaviour that can be taught. Treat it as any other training and think of the restaraints before you think of the end result! This is one behaviour - if you are a strong Alpha - that I agree food can be useful.

Baby food is the best thing to use in this instance as you can dot it in tiny amounts wherever. Be sure that you ask for a behaviour the dog knows first.