The issue wasn't whether Coke and McDonald's care about their consumers' health. It was simply that there is more to these brands than marketing. They're providing a product people really like. It is like cocaine. There is substance to the desire, which doesn't mean that its a morally or ethically justified desire, but means that it's not imaginary and it's not simply the product of emotional or psychological manipulation.

Do people want to do drugs as much as possible? Yes. Do people want to pretend that candy is normal food and eat candy for every meal? Yes. Coke and McDonald's are supplying the latter demand. It doesn't absolve them of responsibility and it doesn't mean they're not manipulative or dishonest. It just means that there is a real, physiological desire backing their products that's not artificially created by cartoon clowns or polar bears.