It is on the other hand very hard to pirate software that only runs on some server. Also quite easy to force a monthly subscription if you simply hide app behind a login screen. Additionally your webapp also has the data of the user hostage so the user can not switch to a competitor.
So basicly I think webapps are a dark pattern. The user of course prefers desktopapps but due to above reasons there is hardly incentive to build them.
Will this change? I think so yes. Eventually this whole Saas bubble will burst, because - Chrome filesystem API will make building a desktop app as easy as a webapp - Open source and crowd funded software will pay the bill for those making desktop apps and users will be more then willing to switch.
When will this happen? If we are lucky within 5 years, but more likely 20 or 30 years.