1K-SFO: I've observed that the concierge also offers rebooking assistance 'behind the scenes' if your flite to us or within US is messed up. The int'l concierges in DEN work in a part of the 1k room so you can generally watch what they do if you sit there. (assuming you are interested in things like this, as I am). Several times in unusual ops, I've seen them protecting their pax on other routes.

I have experienced concierge service in Europe as well (no golf carts) but since I had only carryons was a quick escort to the baggage area and a see ya later.