I also do the RSS/Recap posts, for me I do it for two reasons:

• Somebody else writes something really insightful/interesting/worth sharing
• It's a piece of news/deal that I think is worth mentioning but not dedicated a whole blog post to.

It's a nice way to give some traffic to smaller blogs/bloggers and encourage them to keep posting quality content. It's also a way of me to relate news/information which I know some readers will find useful, but the majority will not.

I assume Gary does it for similar reasons, but I don't presume to speak on his behalf. Personally I like those round up type posts.