Native apps are better, sure. But as a developer, do you really like porting apps and maintaining duplicate code? I'd rather invest my efforts in CSS styling HTML 5 to get a very nice looking interface than maintaining one app with 4 different code bases.
But you have a point. People never liked Java desktop apps. But part of it was that you had to install the Java runtime and they didn't have the familiar .exe extension.
With HTML 5 you can just plug it into an embedded browser and let users download that. Then you can add a hybrid approach where you add some native features such as notifications and camera support while the main content is HTML. Plus, designers can work a lot better with developers on the web paradigm.
