Yes, it’s a questionable choice, but they simply assumed most people would have (at least) a type-A port available on their computer, and fewer would have only a type-C available. A reasonable assumption few years ago, but with the rising popularity of type-C connectors, I guess they should start including a type-C to -C cable in the box in the coming years.
But in the meantime, yes, you’ll need to buy one.
Don’t cheap-out on the cable - the cheaper cables are often good for charging only, no data.
As most vendors, they do not recommend using a USB hub to avoid support issues, but I use one myself without issues. Avoid if you can (keep it simple), but most ‘quality’ hubs will work fine.