Pick me! Pick me!

I’m a member of several QA-related groups on LinkedIn, and I receive periodic update emails listing the discussions in the respective group. Often times, there is one or more posting in the group along the lines of, “If you want to expand your network then please invite me to [email address]. II will accept your Linked In invitation.”
In some cases, these posters are recruiters, and I can understand their business reason for having a large network of people who they don’t really know. In other cases, though, the poster seems to be some QA-related professional. I don’t understand how these individuals think they can benefit from having a large network of strangers.
Any ideas?
One related observation: most of the these posters seem to be in India.