If you remove the state from capitalism, it's merely a system of voluntary exchanges of subjective value. Yes, it is predicated on ownership of resources, but to suggest that everything be communally owned to 1.) to suggest that we don't even own ourselves or our bodies and 2.) impossible to enforce without a state.

If I catch a fish and declare the fish to be "mine", and am willing to defend this claim with force from anyone who would contest it, I hold the position defending my property from those who wish to violate it is not an act of aggression. It's purely defensive. If build a fishing pole, I've created a means of production by mixing my labor with unowned raw materials. Why does anyone else have a claim to either fishing pole I created, or the fish I catch? If I don't own the product of my time and labor, how can I be said to own myself? How can I be considered anything but a slave, living at the pleasure of the rest of society?

If I catch more fish than I can eat, then trade it with my neighbor who grew more apples than he can eat, that's capitalist exchange. And we both walk away wealthier for the experience since I wanted apples more than those fish, and vice versa.

If he hires someone to pick apples for him in exchange for a portion of those apples, that's wage labor. If someone else wants to go find suitable land, plant an orchard, tend to it for several years, they can do the same themselves. The capitalist owners of various means of production invest time, energy, labor, capital, and shoulder risk in order to create excess, which they can then exchange to better their own situation or reinvest in some way.

I'm unclear how someone who denies the legitimacy of property rights considers this sort of activity "violent". It's mildly arbitrary, since nothing in nature is labeled, and no surpreme creator doles out resource. But it's the most effective way to distribute scarce resources in society. If someone mixes their labor with an unowned or lawfully procured resource, I don't think it's at all unreasonable to allow them to claim ownership of that property. It certainly makes more sense than the idea that no one owns anything, or everyone owns everything.

And you certainly can't distribute resources without either a propertarian system as described above, or a centralized bureaucracy to decided who gets what. That's why left anarchism of the communist variety makes so little sense. After all, who is going to keep people from claiming ownership of things or engaging in voluntary exchange but a strong government willing to use violence to preserve the communal ownership of resources.

How these lines would be defined in a society free of rulers would probably vary from region to region and depend on local culture and customs, but the idea of polycentric law is a whole other topic.