Just a clarification here: you can absolutely bring back Tequila and wine. The one liter of alcohol limitation per adult is just the amount that is duty free. You can bring over that amount for personal use, just declare it to the CBP officer when getting off the ship. I bring extra alcohol on pretty much every international trip or cruise, always declare it and have NEVER been asked to pay the duty and taxes on the overage.
This is because the duty and taxes on a bottle of wine or Tequila is around $3. The CBP officers are just not interested in doing the paperwork for 3 or 6 or even 36 dollars (when I brought a case of wine home). I always know that if they do want to charge me, I'm happy paying those 3 bucks or so a bottle. But it has never happened.
So, feel free to stock up on liquor to bring home, as long as it's for personal use! (DO NOT fail to declare it to the CBP officer, because the "failure to declare" fines are far higher than the otherwise due duties and taxes.)