My own problem with services like this is that I don't want to tell their owners what blogs I read. It's a privacy concern. I'd feel much more comfortable using a standalone tool that I could run on my own laptop (ideally one that didn't require running a web server or even a web browser).
Even stripping everything out but plaintext with an HTML parser to put it in a text view, I realized I could wrap the links with native Cocoa labels that act as hyperlinks. And then do the same with images. Hmm, what about tables and stuff? Soon I realized, why would I even want this? It's annoying to visit the origin site when the RSS reader can just render it, and it kinda defeats the purpose.