Crusied carnival twice. Both times brought aboard 5-7 bottles of wine, and a case of bottled water (we just put a luggage tag on the plastic wrapped case).

You should not have a problem putting a fifth of your favorite beverage in checked luggage. Transfer it to a plastic bottle and if you're paraniod, put it in a ziplock.

Never bothered with beer due to the issue with keeping it cold.

Coke cards are a good deal as long as you drink about 3 a day or more.