I'm an Amex Platinum customer and recently used their Platinum Dining service to make a reservation for a Saturday night dinner in East Hampton. First time experience, and the Platinum Concierge was able to get a reservation lined up that was superior than anything we could get directly from the restaurant. As far as I can tell, this was not one of their standard/preferred places. (We named the restaurant upfront and asked them to see what they could do.)

My question is: how did they do this? I'm asking more from a business model standpoint than as a customer. In other words, what motivated the restaurant to give better treatment to Amex (on my behalf) than to me directly?

From what I understand, Amex outsources this service to Circles. But, what does Circles do that actually gets the attention of the restaurant enough to help us?

Just curious...