GronchoAs Tigerman eludes to, you can just sharpen flat. You're confusing the grind with the edge. Many production knife markers put a hollow ground because in some ways it's easier to manufacture and the customer doesn't have to remove as much material when sharpening. I honestly dont know of a blade that has a hollow ground edge other than straight razors or reed knifes (for woodwind instruments ). The edge otherwise folds too easily.
Is the best I can find. Looks like the idea is you create a secondary bevel rather than trying to hone the curve itself.