Co-ops are of course worse for investors. There are no voting stock in co-ops, so the stockholders can't squeeze maximum profits off workers and consumers.

Europe had very strong socialist/non-capitalist political movements in the 19th century. Co-ops were seen as one alternative to capitalism, and were a huge movement.

For example in Finland the largest bank and largest retail chain are (consumer) co-ops, and in general co-ops are big players in the economy.