What's amazing is that Americans don't live in a purely capitalist state. Nobody does. Every major country in the world has a mix of capitalism and socialism. AFAIK no country has purely private firefighters. UPS and FedEx exist, but so does the national postal service. In many countries various utilities like water, sewer, electrical, etc are publicly owned, but in most places the phone service is private.

China initially went full publicly owned, but it was a disaster, so they now have a mix of public and private. Cuba has had to open up its economy to allow privately owned businesses. Meanwhile, the US learned long ago that purely private is a disaster. Policing used to be private, run by companies like the Pinkertons. Firefighting used to be for-profit only.

90% of people campaigning for "socialism" are talking about European-style socalism, at least as a first step. A social safety net. Healthcare provided by the state. Utilities owned by the state, or at least heavily regulated, etc.

But, Americans, while they love the fire department and couldn't imagine replacing it with a for-profit fire service, somehow think the economy will collapse if the government opens a grocery store.