This is a very limited view of government; today everyone agrees that the government should be allowed to tax things that harm us such as alcohol and tobacco. These, like fat, only indirectly harm others.  Attitudes towards fat are changing as the problem becomes much greater. It is now accepted that when people do things that harm others indirectly the government must have a role. The rise in healthcare costs creates just such costs by increasing the cost of the healthcare system as a whole which is either paid for by everyone through taxes or passed on through higher insurance premiums.