Understood, because the membership rules allow you to pay for extra guests. This will be different, because the membership will be invalid at that location. Priority Pass handled this when United Clubs accepted some, but not all, types of memberships.
That was the origination of Priority Pass Select, right? So I guess this would be Priority Pass Select Select
I would skip the SFO Centurion and go to a PP Restaurant. I figure it "helped" AMEX with crowding. I guess that was too expensive. I'll still do that with my Chase Priority Pass membership (for now).