when we were there in april new packs of coffee were left for us each day by housekeeping...no charge. there was a notice saying you could purchase more for a price, but i think this would just be if you were going through more than the one pack a day they leave you.
On each of my many trips I have found housekeeping very responsive to coffee needs. When they notice us using the packets they tend to leave 2-3 extra the next day, never a charge. Service at this resort improves with each stay and is top-notch!