I think I have been DCC'd on an Advanced Purchase at a Hilton-family property in EU. From my credit card statement, it's not clear if I had indeed been DCC'd or just have a crummy exchange rate. Of course, you have no choice given and the only recourse maybe to dispute the charge, but I sort of anticipated this, and the damage is minimal (likely $6, I won't bother). Lesson learned though, use AMEX if this is an option even for an advanced purchase.