But nobody is saying that everyone has to be equal. Coops have measurable pay ratios just like everyone else, they just tend not to be as large as non-coops. More important (or harder to find) roles will obviously get paid more.

At the end of the day, most people want to get paid, and to get paid, at least in the long term, you need a viable business. So workers tend to make choices that ensure the business is able to survive, because that is more valuable in the long run than lining their own pockets right now and not having a job to go to tomorrow.