Tipsy taboo. I particularly noticed:
A handful of scholars permit alcohol as long as it is not made from grapes and dates, because these are specifically mentioned in the Koran.
I had run across this concept exactly once before, in Poul Anderson's 1971 novel
Operation Chaos. From a scene in chapter 5:
"I believe you are concealing something," went on the emir. He gestured at his glasses and decanter, which supplied him with a shot of Scotch [This is a world of magic], and sipped judiciously. The Caliphate sect was also heretical with respect to strong drink; the maintained the while the Prophet forbade wine, he said nothing about beer, gin, whisky, brandy, rum, or akvavit.