I think the OP was referring to people who are offered the treatment they want then just don't turn up for their operation and also don't bother to let the hospital know they aren't going so the hospital can schedule someone else for the time.
As it is that slot is wasted when there are many thousands of people on the waiting lists who would jump at the chance if it was offered to them.
I don't believe anyone was suggesting a person should be denied NHS medical care just because the happen to smoke or drink or be fat.
Should those that don't turn up without good reason be charged for the wasted costs, would it focus peoples minds of taking the opportunity to have the care their body needs when it is offered?