BourneIdentity:
You've hit the nail on the head. Especially on the obesity/gluttony point. The Bible defines gluttony as "over eating". Obesity easy easily identified. If you over eat you will be overweight. Gluttony is a sin and specifically mentioned in the Bible. Do you know what isn't specially mentioned? Smoking. Yet your will be disfellowshipped as a Witness if you do the latter and not if you are the former.