Earlier quoted context omitted.
I would imagine it comes down to having the initial capital to start such a venture. Those with the capital retain ownership and reap the future returns. If there was a way coops could raise significant funds to start say a big box chain store, we might see more of them. I don't think small business loans quite cut it here.
If this is true, I wonder if this is inherent in the way markets work, or a result of the way we (government, society, whatever) have structured things.
On the one hand, the market remains this way where people with money are more easily able to make large sums of money through investment, by making their money do the work. The system in this sense is self-perpetuating, but strictly speaking, doesn't have to be this way.
On the other hand, as a thought experiment, imagine a magic wand was waved and all capital and resources were evenly distributed across the national or even global population. The world would still be left with an inequality of people's ability to earn each others money. Those with good health, savvy business sense, in-demand skills, and knowledge of production would quickly start down the path of quickly earning, while others are left only spending. I don't think it would take very long to end up right back where we are today.