I am in Las Vegas and went out to dinner last night a the Public House, a fantastic restaurant at the Venetian.

We were having a great meal when several of us decided to check in on foursquare. (Hey, we’re from San Francisco, we do dorky things!) We noticed a check-in special for a free house beer with purchase of an entree. All of us had entrees, so two of us decided to get beer.

I asked the waiter for the house beers. He pointed to the beer list and we ordered.

When the check came, we showed our phones with the offer. He then told us that the offer was only good on a specific beer, not the beers we ordered. (There was no mention of this on the offer.)

This added some friction to an otherwise pleasant meal. He also went to check with the manager who refused to do anything. (It would have been $15-20 on a $210 tab.) He also told us that we should have showed our phones when order the beers so that he could direct us to the discount. At a fancy restaurant where I’m out with friends, I don’t want to have to show a phone for a discount, especially during the meal.

While I understand the need to have restrictions, there is the tradeoff with the consumer experience. One of the things I love about the American Express approach to offers is that I don’t have to worry about whether I get the deal I was promised. It’s automatic as soon as I swipe the card. There’s no presenting anything, there’s no arguing. From a business owner’s perspective, this adds a number of benefits: no staff training, no POS integration and a better guest experience.

And I get a confirmation within seconds of completing my transaction.