This company appears to be catering to markets (C) and (D), and would be a drop-in replacement for whatever other stovetop they currently have. Most likely it can be a DIY self-install with the exception of capping a prior gas line.
If you require the user to cut new holes in their fancy granite for your custom knobs, they lose the option of going back if they don't like it.
There are some extremely-high end cooktops (e.g. Gaggenau) do require the additional cutouts for controls, but they have already proven their brand with high-end users so they can pull that off. A startup can't.