Most homes have either a desktop, or a laptop, or both, sometimes multiples of each.
Every business has at least 1 computer (desktop or laptop, sometimes multiples of both).
So there very much so is a lot of money still in desktop.
Right now if you want to purchase a factory Linux computer, your choices are severely limited. It's either System76, or the Dell Sputnik (which for some reason costs more than it's Windows counterpart).
XP just expired. My company has a warehouse of 40 workstations running XP. We're looking into getting new hardware. Guess what... it'll be Windows because there are not many other options to price-shop around and/or get differing levels of support.
There is indeed money in Linux Desktop.