I'm a member of a social network that is ok, not great. I went to add friends based on my gmail contact list, assuming it was only going to send friend requests to those in my mailbox who were already on the system....NOPE!
I ended up sending an invite to every person in my gmail contact list. I definitely would not have targeted 70 or 80% of my network for invitation into that network, but so be it.
The net result is I likely brought people into the network who aren't particularly interested in it and may not be a fit for it. It's one of the many things that I think are troublesome about social networks and their effectiveness. Except in this case I'm part of the problem.