It seems that pawns with chemical fascination only ignore drug policies about not taking drugs, but if you remove beer from their food policy restriction, they will no longer randomly drink it.
Repro:
1. Get pawn with chemical fascination on "no drugs" policy
2. Get pawn low on recreation and set recreation time
3. Draft/undraft to reroll recreation plans
Do this with beer allowed and beer disallowed in their food policy. They will follow the food policy. Since the trait says that they ignore directives to not take drugs, it seems this should also extend to food restrictions and not just drug policies.
Both DLCs, no mods used.
Thanks for this report. I will see if this is intended or not. It may be intended since a pawn can still have a drug binge and drink all the alcohol either way. That satisfies the 'ignores policies about not taking drugs, but I will run it by the devs either way.