Since bananas require fewer steps from farm to being ripe for consumption, the supply chain of bananas is naturally less complicated than that of coffee. Where coffee needs to be grown by a farmer, sent to a roaster for roasting, then shipped to the retailer for sale to the consumer, bananas only need to be grown and shipped to the retailer. Since there are fewer outlets to go through in the process, the banana industry can move its product from farm to consumer at a much lower price than the coffee industry can with its good. The banana growing process is also more straightforward and repetitive, so all part of the process can be reused in one way or another. The old banana plants can be used as organic fertilizer and the plastic wrappings, although not ideal, are reused from plantation to plantation.
The main threats the banana industry faces is their excessive use of chemicals and the difficult nature of the work required in the banana growing process. Many chemicals are required to keep the product ripe and protected through delivery, and it is seemingly unavoidable to use these things. Further, the work on a banana farm is intense, physically taxing work that requires several hundred people per farm. That being said, I would rather work on a banana plantation than on a coffee farm because it seems more straightforward machete work or sorting bananas than the time consuming process of picking coffee cherries one at a time.