This is fine, I guess, if the Government ensures that all taxes paid by the individuals concerned and applied to the NHS are repaid. By taxing them in the first place, the Government denied them the chance to make their own health care provision. To deny them treatment now is outrageous, unless they are given their money back to buy private service.
Personally, I would be more than happy to take up smoking or whatever if I could get back my taxes and pay for proper, non-socialised, health care myself.
Telegraph News NHS may not treat smokers, drinkers or obese