I would rather have the convenience and speed that is an obvious selling point of ApplePay and try to be aware of DCC in the <1% of transactions that I make in a different country (and I do quite a bit of international travel... but I mainly use cash).
If there are other examples of discrepancies between the displayed and actual charges, it might be helpful to point them out to those of us that aren't aware! But if DCC is the most notable one, I'm not too concerned and would prefer not to get an extra prompt.
For instance, in the video during its introduction, Apple Pay was shown being used in an ideal situation. I've had that same experience at several merchants (mostly those that were brought out as "launch partners", like McDonald's). Having a different experience at some of the retail partners seems to be "fragmenting" the user experience.