You can buy wine and liquor pre-boarding and have delivered to your room. I purchased Bombay Sapphire for my cruise on Jewel this past January.
https://www.royalcaribbean.com/royalgifts/wine-liquor/alcohol-packages
Submitted my request via email yesterday at 4:47 PM, received automatic reply back at 4:48 to allow up to 21 days. Went to the Princess app to look at excursions 20 minutes later and the OBC was added for my cruise in October.