I know sometimes it feels like that. But I think sometimes there can be several people in the room, and only two of them know each other, and it makes it "feel" like everyone knows everyone and you are the odd-man-out.

Also some people are just naturally chatty, and if you are generally quiet it can feel like you are left out. This happens IRL too.

If you really feel like chat will be beneficial to you, you can always go in, and if you don't feel comfortable in the conversation, try moving into one of the other rooms there, one of the empty rooms, and someone may follow. This way you can be a part of a fresh conversation. If no one follows you to the new room, it is probably because they are assuming you are planning to meet someone in there to talk privately. You can always tell people in the main room that you are moving to a new room, and would like some company, or that you need to talk, and see if that attracts people.

That said, some people just can't get comfortable in chat. Nothing wrong with that, that's why we have the forums here too. Different dynamic, different feel. I see some people who seem to be in chat a lot but don't post on the boards very often.