We told them we what we were doing (star service) and left the sodas, wines, beers, etc next to the TV. I don't remember if they took them away, but as we went through our own beers and sodas, they restocked the mini bar for us. We were only ever charged for the one soda which we did drink.
Here's another thing we do on cruises where you can't bring anything with you: we have our room steward clear out everything we don't want out of the mini bar and just stock it with stuff we DO want. This way we have Coke, Diet Coke, Miller Lite, and Coors Lite handy, and none of the fridge space is taken up with anything else. I'm sure they'd do that for you as well.