by nerman8r
The cards that give you points for certain combinations happen when you resolve your dice, and that only happens once. It's a passive effect that is triggered at the time. Even if you didn't want the points, you would have no choice.Energy Drink, on the other hand, is saying you can pay a cost to do an extra thing. You choose when it gets activated, so there's no limit to how many times you can do it, except for your energy supply.
Ultimately, I have no "proof" that this is how it works, but I do play Magic: the Gathering, which has thorough rules for how everything works, and the KoT cards are designed the same way by the same designer. I'm pretty sure Richard Garfield and the folks at Iello would agree with me.