And that's their prerogative.
But, as I've said before, I believe that some content belongs where it is posted and doesn't need to be aggregated back to the mothership.
The problem is context!
Yes, being able to feed replies, and even whole conversations, back to your own site can help but is most beneficial to the original poster.
It's good for me to have all replies from micro.blog fed back as comments on my post; each of those comments depends on the OP and belongs with it. But do they truly belong on the commentor's own site, isolated from the post they are a response to?
Hold up a second. You're probably thinking I'm being hypocritical as I post "replies" on the blog. So what's the deal?
There are degrees.
There are different types of reply and they should be treated accordingly.
Social replies like on Twitter or Facebook don't, in my opinion, need to be owned - they belong in the context of the social network and that particular conversation.
If they contain something meaningful, perhaps a specific point you want to share further, then they can be rewritten as a blog post which creates a new context for it.
Then you have the longer replies, posts in their own right, inspired by, riffing off, or in response to, the original. These have a shared context but are more standalone and deserve to be owned.
They are what blogging conversations used to be made of before the social networks stole the conversation but, thanks to things like webmentions, can also exist as comments on the original.
(Without the need to copy/paste.)
It's good to collect the important stuff but we should pay more attention to that context.
Just as not everything needs to be pulled back to your own site does it all need to be pushed out and cross-posted as well? This is something I've been wrestling with for a while, especially in the context of micro.blog.
Currently everything from the blog ends up there but does it really need to? And if the answer is no (which it probably is) how is that best managed without introducing a layer of complexity? A layer that detracts from the simplicity of posting.
Perhaps I'm overthinking it but I think we need to draw the lines somewhere.