You don't really need continuous contact between hoop and clamp, and trying to match curvature would require different clamps for different size drums. I like the design, and am glad to see this. I might buy one myself. Losing the small floor boom would save some weight in my mic bag.
I think you're right. Or not. The engineer part of my brain (very small) can make a case for either option. I wonder if there was some miscommunication between the designer and the manufacturer? Hmmmmm . . . . . .This looks pretty neat, but: Am I crazy, or is the curvature of the clamp part exactly the reverse of what it should be? Should it not follow the shape of the hoop?