Almost the entire world economy, by value, consists of more competitive markets than US healthcare. Restaurants, yes, but also the rest of retail, energy, agriculture, transportation, mining, metals, automobiles, clothing, shipbuilding, forestry, fishing, custom manufacturing, industrial food processing, scientific instruments, electronics, electrical equipment, and the financial markets. Some of these sectors don't engage in wage-labor production, or aren't dominated by it, and so aren't capitalist, while others are. Actors in all of these sectors, even the noncapitalist ones, engage in lobbying and other forms of anticompetitive behavior, but they generally aren't successful in obtaining monopoly or monopsony power and thus ending capitalism where it exists.

Sectors that lack competitive markets include the military, healthcare in much of the world, banking, and most of telecommunications.

I agree that business (not just capitalism!) creates incentives to destroy free markets, just as politics creates incentives to destroy democracy. When actors succeed in following those incentives, that ends capitalism by eliminating competitive markets, which prevents the price system from being used to allocate resources. Competitive markets and the price system are central characteristics of capitalism; where they fail to exist, what you have is not capitalism, but something else.

At this point I'm starting to repeat myself, because I've already explained this about as clearly as I know how, and you still apparently don't understand.