Young pups really shouldn't have treats of any kind (including chicken sticks). They best way to reward him is with a piece of his own food. Now that he has a taste for baby food you are going to have to do it cold turkey. No chicken sticks!
Make sure you are feeding him the healthiest food possible and stick to it. Check out your ingredient lists and decide if you think those things are healthy for him.
Pet food manufacturers have found that they can make just about anything "nutritionally balanced" by adding a bunch of synthetic vitamins to the mix so use your common sense when looking at what the food is made of and how it was processed.
Sometimes it helps if you don't feed him when you have people food out or have been cooking. If they smell you food it often gives them the idea that yours would be better than theirs. Maybe try feeding him in the morning before the smell of other foods hit his sensitive nose.