First, just to clear up any confusion, there is no "wifi" in the rooms, it's wired internet access.
It is free now for members, and you shouldn't have to go to the desk to show your member card. When you log on, it will say that there's a $9.95 access fee, but it's waived for members and should not appear on your bill. If it does, then you'd go to the desk to have it removed. We've used it 3 times since the fee has been gone and have had no problems (SSR, HHI & OKW).
Techincally my understanding is this benefit is only for members (and staying on points not cash), but there are a lot of reports of non-members that have stayed on points getting the free internet. I would say that your friends may or may not get free internet and should be prepared to pay for it if they use it.