CKB, that's just an easy way to reproduce it. What is happening is that I'm using a photocopied monster, YRing it, then trying to drink.
The bag is triggering on the photocopied monster, and preventing me from drinking.
Version r19136
If your script does something like the following, mafia will abort once it gets the doctor bag quest start NC. Instead of eating, it will print "you are currently in a choice." This happens even if you have the choice set. It doesn't matter if mafia is set it to accept the quest...