As a content delivery platform, the web is unparalleled, ridiculously good. I have paid for content (for example, NSFWCorp), and will do so again in the future.
But as a software delivery platform, the web is unproven if we are to be kind, and crap if we are to be honest. Web software is fragile, limited, and subject to the whims of the site maintainers, who may modify it without warning, or even remove it entirely (e.g. Google Reader). I have spent hundreds of dollars on native productivity software, games, etc. but I have yet to spend a dime on a website for its JavaScript.
That may change in the future, but I doubt it: any program that's a sufficiently good web app can be rewritten as a desktop app with more capabilities. Ultimately the web may be the go-to place for trivial or gimmicky software, but the most powerful apps will be peers to the browser.
Everything has to go through the centralised, closely guarded app shops. You'll have to go through silly certification processes to get your app into the app shop and if the platform owners (or some minion working in certification) feels like it, they can just remove your app without warning.
Compare this to a web app. You deploy the stuff on a web server of your choice, the user clicks on a link. Done.
Exactly. The humble hyperlink is the most amazing thing about the web. It's simple yet devastatingly powerful.
I'm not a snob about the programming languages of the web. I don't care what language I need to learn to create content for the web, or what tools I need to use. The language and the tools will always be a means to an end — that is, the radical ability to provide free and instant access to any content for everyone on the Internet.
(from a blog post I wrote "why I create for the web": http://blog.neave.com/post/64669185529/why-i-create-for-the-... )