Not every company increases wealth though. Selling addictive poison (cigarettes) for example does not increase wealth.

I agree this is a good example.

Another one is weapons selling companies.

But even then a strong case can be made that without those companies people would still satisfy the demand via black market causing same harm bit without money benefits to society.

So still it is better with companies than without.

It does increase wealth for shareholders. This is why there is so much capital allocated for opioids as well as other extralegal pharmaceuticals.

I thought we were discussing total wealth and not wealth for some portion of the population, at the cost of somebody else's wealth (computed holistically, not just money but also health and overall wellbeing). By this logic, stealing increases wealth of the thief.

Wealth creation is not a zero sum game.

Except directly stealing - wealth is created.

For example — even if all the profits from oil on earth goes to few pockets it is still benefitial for the world.

Because those pockets still gonna spend those money one way or another and contribute to economy growth eventually.

This is how Russia was flourishing on 2000s - oil profits mostly wen to putin's gang, but ordinary people quality of life still grew substantially.