They are pretty useless unless e-powered, so the cost is like 5k upwards and it's kinda only useful on occasion. They are big and you have to store them somewhere. They are also kinda single-use once in a while. So target user groups are either deliveries, where it's a special kind of cargo bike or above mentioned rich people who have a spot on a pavement to park them.

You don't really need a cargo bike, but it's a nice to have.