That is exactly the reason for moving everything to cloud and SaaS: software that is being bought is paid once (when not free), while the one hosted remotely is paid for use, many times, even if it's free (hosting costs). Doing the same thing with operating systems is just the next iteration. We're slowly going back to the mainframes era: a central server that holds everything surrounded by dumb terminals that can't work without connection to the above server. To me this equals to throwing down the toilet 50 years of IT advancement and open networks culture in the name of profit.