Web 2.0 Applications - Reality Check

(Note: It's not my intend to pick on Basecamp here, I'm just using it as an example of a Web 2.0 hosted application)

If I get myself Basecamp it's about 24$ / month. So I pay 12 * 24$ = 288$ in the first year. And every year thereafter.

Plus, I can only work when connected with the Internet. Not in the train, not in the plane (mostly). I need broadband internet access. Plus, if the company goes out of business (or decides to stop the service), I'm hosed. I can't continue to use the product. With a traditional shrink-wrapped package, I shell out about the one year fee of a Web 2.0 app once (or maybe even less), but then I'm free to use it a few years and not upgrade.

Why can't I get Basecamp (which is a really cool product, BTW) as a downloadable app, too? I would be able to set it up on my local machine or on a server behind our firewall with no bandwidth limitations etc.).

Yes, I'm well aware of the advantages of using a web-based, hosted application. But these advantages just don't cut it, IMHO.