E.g.: Chimneys. They're everywhere. All over the world.
Do all those private enterprises try to calculate the 'costs' of lung cancer rates in their workplace and community from all the toxic materials that get spewed into the air? No. Instead, some Capitalists complain that their taxes are too high, and that they feel oppressed by brutal legislation that forces them to install costly particulate filters that reduce their profit margins. Even though I've never been to China, I heard that their air quality can be quite bad in some places. Maybe their government doesn't care if some of their citizens get slowly poisoned. But what about all the Capitalist companies actually responsible? They don't care either. We were promised that "private security" would fix this sort of thing!
Thank you for bringing up China's air pollution, because that is a perfect example of government doing the opposite of what you hoped.
If we were living in an AnCap world, and a factory nearby was polluting your air, you'd be pretty pissed, right? You might even go out and ask them to stop, if they ignored you, go and protest them, and if they continued to ignore you, maybe even turn to sabotage and violence. I mean, they are killing you with cancer causing chemicals! More-so, they are doing it to everyone in the area, so it wouldn't be just you doing this, it'd be a whole mob. So either they will be taken out, or else they would have to hire their own private security, which would make business much more expensive for them. And the more they pollute and piss people of, the more security they will need, meaning $$$ out of their own pockets.
But we are living with a government that has laws and regulations. Sadly, this company that's polluting your air is not breaking laws, and is complying with regulations, likely because they bought a politician, and wrote the regulations themselves. And if you go and protest them or try to fight them with sabotage our violence, they will be defended by government police. Police which, by the way, you paid for with your taxes. So, they write the laws, and get you to pay for that law enforcement yourself. Sweet deal for them, but sucks for you.