The force of habit is very hard to kill. The only sure way to eliminate it is to overwrite it with another habit or reduce it very slowly. An example to that slowly reducing what you eat, like you go 2-3 cups of rice to 1 cup of rice per meal or slowly switching from white rice to brown rice by a month or so. It won't work if you immediately go 1 cup per meal at day 1, your body has no time to adapt and within a few days, your body is too weak to resist temptation.
For this kind of habit, I think a perfect way to eliminate it is finding other things to do in the morning, like maybe tending his own garden and such.