I agree the tooth brushing example was detrimental to the point of the post.

You could also say, I put on my underwear after drying off merely out of habit and the underwear cartels make their cottony underwear so smooth merely to provide a pleasant reward for my ass cheeks. But, in fact I put on my underwear for a variety of practical reasons and the smoothness is not really a reward.

The snack break example was more to the point. That's a voluntary thing that becomes routine, but could be skipped with no social repercussions.