It's DHL. If you want your package or pallet shipped to some island it might take a long while until a big container ship makes the next stop there. If it can stop there at all. For a package/freight company, the capability to run ships on your schedule to small harbors is valuable. And a catamaran could be a competitive alternative to other smaller container ships
What I don't understand is that they are talking about running it trans-Atlantic. Taking longer than a normal container ship, while taking less cargo. You save on fuel, but surely the crew costs must be eating up all those savings. And you're not really faster. Unless the plan is to go point-to-point between smaller harbors, making up any lost time by saving on cargo handling time
Your crew isn't emitting hundreds of tons of CO2 burning the dirtiest fuel available on earth, though.
You might not need much crew for a vessel that small. Automation can take care of most of it, and with the right equipment the ship can basically sail itself. Then you just need a captain and maybe some maintenance crew to keep the automation running.