Same here - Avis in France, I even have a copy of the contract saying that I want to be billed in Euro, still billed me in my home currency.

In the US too - Ross dress for less - I didn't even have a choice to opt out DCC.

This DCC is a scam and merchants love it because they get 1% of the profit (I found it on a page from the Danish payment company PBS).

So I really checked my bill right after the transaction, and bring some more cash - I rather get robbed by changing cash than this DCC scam.

If Marriott does this to me, I'll definitely file a complaint because this is purely unacceptable for a big and established chain like Marriott.