Read what you can and don't worry about the rest. The chances that you'll see something worthwhile in a feed are far, far higher if you've subscribed to it than they would have been if you hadn't.

Some feeds are really important and are best read outside of the bulky environment of a feed reader.

If instead you offer people a FeedBurner feed of shared items, you can plug any RSS feed in as the source for that feed. Bookmark items "toshare" in Del.icio.us and grab the RSS that tag in your account produces - publish that through Feedburner and you can know how many people have subscribed.

There are so many different ways you can use RSS feeds. Here are a few of my favorites, try experimenting and you'll get more out of the medium.