I don't think they are bad. It's just that the administrative costs of running the coop comes out of the price leaving less for the farmers. Plus, there's a cost to the farmer to buy into the cooperative, which puts them out of the reach of some small farms. On the other hand, there is less risk to the farmer in that they are almost guaranteed to sell their crop. Direct trade tends to get more money directly to the farmer since there are fewer middleman and admin costs. But, there's risk to the farmer if her or his crop does not meet the exacting standards of the buyer. Much of the generic coffee is fair trade, although they may not advertise it.
There is a huge human cost to our coffee obsession. https://dailycoffeenews.com/2013/07/17/farmworkers-left-behind-the-human-cost-of-coffee-production/