I'm sorry, I don't really understand what you mean here. If they don't want to 'follow' you, why would you expect to send them things?
> I can really just group the input feed, not the output feed
You can choose which circle(s) you wish to share with, is that not controlling your output feed?
People can filter their input (who they have in their circles) and their output (which circles they share each piece of content with).
I suppose you can't follow a chosen subset of a single users output, unless you can do something fancy with tagging.
Don't you get recruiter spam through Linked In? What about the more general advertising and marketing industry? They survive off such a model.
> Don't you get recruiter spam through Linked In?
Yes, the rate of which makes LinkedIn just an inbox for job offers for me, not a social network.