Historical practices are not counterarguments against for profit models of medicine. Even if it was, historic non-profit models do not scale.
Doctors for profit might not be the only model, but I'd like to see you propose any other model that actually works.
> Eating right plays a very important role in health and welfare and you don't have to wait until you are sick to wonder if your diet could stand to be improved.
Er, you do know most people are either overweight or obese? It's once thing to know what's right to do, but people don't do it or spend money on it.
That's because people will pay for a cure / treatment when they are sick. Unfortunately they won't pay for prevention so that they wouldn't get sick in the first place.
Besides doctors can't guarantee a resolution, they can only guarantee treatment. If doctors would get paid only for a cure, it would just create different problems. Some people would be refused treatment because the odds of getting paid would be too low, others would have their treatment stopped because continuing would likely be unprofitable and only large institutions would be able to afford to provide services since only they could play the numbers in order to statistically stay profitable.