It definitely benefits them. Being overweight is caused by overconsuming. The most effective way to combat it is to eat less, which means consuming less. That's not good for business. So instead, everyone pushes exercise as the sole solution to our health problems. Companies like Coke push exercise because that helps them sell more sodas, and then companies like Bowflex push exercise because it helps them sell more treadclimbers. No brand is ever going to encourage you to buy less of their product.