The case could be made that Corel did this to make it easier for users who used one product to find things in the other. I use both macs and pcs and I still get confused because the command button is on the inner while ctrl on pcs is on the outer. You need cmd-w to close while you use ctrl-w on pcs to close. I really wish one would copy the other and make the exact same keyboard.

The layout in Excel is not special or better than other layouts. The point of patents is to protect ideas that are unique and improve. By enforcing patents on layouts which are not specifically improvements, you're really just trying to create an artificial moat that makes it harder for consumers to switch products or use more than one. That is bad for consumers and it hurts innovation.