Not sure if you missed something out here. IIRC you don't pay any interest on foreign card transactions, only on cash withdrawals.
Why are you buying food and drink in an all-inclusive hotel

I think you're doing it all wrong...
EDIT: Also worst advice ever, why would you even consider carrying that much cash around? Do you nip out to the shops here with a grand in cash in your pocket? What if you got mugged abroad? Or your hotel room/villa/wherever got broken into, and your cash was stolen.
Where the majority of places in the world accept card (even 3rd world African countries) it's just not worth even carrying cash around.
A backup card is a bit over-cautious

. I've been using my clarity card for many years without a backup card. Well i should say a cost-effective backup card. In the most extreme case i would just use a normal card and suck up the fees. Although my partner does also have a clarity card in the event that i lose mine whilst abroad.