[pawelwentpawel]

There is quite a lot of recruiters/randoms just adding as many people as possible. Without any introductory message, I would just consider that as spam. However, if you know somebody in person but don't know him very well then I don't see a huge problem. I get quite a lot of invites from my former class mates that I had no real connection with. But hey, you never know where your life takes you. Those connections might accidentally come in very useful one day.

As for the recommendations - they've got nothing to loose really. In the worst case they won't get one.