There’s been a long-running idea that duty free items could be picked up at the other end. That would mean them travelling in the hold or secure storage in the cabin, or even bought from an exit facility at destination. Anything purchased on board could be handed over when disembarking.
This would a) stop people drinking the contents on the aircraft and, more seriously, b) stop passengers evacuating down the slides in an emergency with bags full of glass and flammable liquid. If picked up at the far end, it would save quite a bit of weight on the flight, too.