Being Greeks I think We beleive anyone who comes to our doorway. UT-Knoxvill is a proof in point.
I used to travel a lot and would stop in Houses.
If You have lost Your Card, You still have a rudiment knowledge of Signs that so designate who may be Members and who are not.
At The Gen. Assemb. that I attended 2 years ago, while I had My Card and Credentials, I still had to give the Grip.
It was funny to see so many Guys practicing it before they were allowed to enter!