LinkedIn is a weird, weird place. There's always people wanting to add me, but then they mostly don't introduce themselves. Even half of the recruiters who add me don't do an intro. How is that networking? The articles seem pretty low quality. Sorry to say it, but a lot of them seem to be written as a form of homework, as in "you should write something to be seen". There's rarely any insightful comments on news piece…
They want access to your contacts list. People are more likely to add someone who is connected to a person they already know/are connected to.