I visited the SFO MLL yesterday with a colleague. I have lounge access because of status + Aeroplan Premium CC, but she doesn't, and I wanted to invite her as a guest. We were flying on the same PNR. SFO MLL has automated gates where you need to scan your BP to get in, and only after the gates you see an agent. I was expecting her to be denied by the electronic gates, but she got through instantly (even scanned before me).

I didn't notice until I went to the agent to ask to get a guest in. Agent looked confused for a second and just asked me "Uh, then how did she get through?" — as if I knew.
Wondering if tickets on the same PNR are "recognized" by these kind of gates, or if it was some sort of a glitch? That hasn't happened to me at other MLLs before.