This scam is so annoying it hurts. Traveling throughout Europe I was constantly offered the option for DCC. Just for laughs I would always as the server or front desk what they suggested and they almost always suggested I use my local US currency or said it didn't matter. I then explained to them that it does matter... and what they are saying is untrue. One nice waitress sat with me while we checked the conversion rates and when she saw the difference she was aghast. She said she'd never again offer it to any customers. Such a scam and so many people are unaware. This should be illegal.