Originally Posted by Majuki

DCC has evolved into a scam when the going rate is now between 4-5%, which is more than the standard 3% currency exchange fee that issuers charge. Since banks were losing out on this, they switched to foreign transaction fees, which we've discussed extensively already, so you're still getting with the 3% FTF even if you accept the 4-5% DCC offer, resulting in a 7-8% markup on your transaction. Back when it was one or the other (and the DCC offer was a more reasonable 3%) it really didn't matter which one you chose, and you might have even come out ahead accepting DCC since the currency exchange fee wasn't calculated as part of your rewards earnings whereas the total amount inclusive of the DCC fee would count. Again, this no longer holds true, but it did in the past.

If anything, I'm surprised DCC isn't more prevalent due to American culture trying to upsell at every possible opportunity. How often do you hear, "Would you like to make that a large for 49¢ more?" "How about adding purchase protection to this today?" "I see you've already got this, but can I interest you in this adjacent service [that's more expensive]?" It seems like every which way they're trying to get you to accept the offer, and some employees even have quotas to meet. The only reason why DCC isn't all over the place is because on average I suspect that few big box retailers see non-USD cards outside of select locations.