Supposing it was discovered that (say) eating a handful of grass every day would ward off cancer. In an RBE there would be much rejoicing at the discovery and studies would look into how we can produce and distribute enough grass to meet this new need, and/or how we could extract or manufacure the active ingredient if that would make the remedy more efficient. The objective would be to derive the most human benefit from the least unit of resource.
In our current economy, the jobs of people who work in big pharma and the cancer industry would be at stake. It would be in the vested interest to discredit the claim that grass cures cancer, or to corner the market in grass, or to monetise it or the active ingredient that brings the benefit. It is easy to deride this need to protect vested interests, but it is a very real need. If people don't have jobs their lives collapse. Therefore there's a trade off of jobs for other gains. The "need" to have a job has to be weighed against other needs.
In an RBE, there is no need to do work for its own sake and if work can be handed over to machines or obviates, that is done as soon as possible. Thus if grass cures cancer and there is no more need for people to work in big pharma or the cancer industy that is good. Those people can do something else.