I've lately been playing an herbalist and using mead to enhance my appraise for selling. I've noticed that even if I just drank the mead, changing servers the buff goes away.
The problem with this is, it narrows where Tavern RP could occur for people buying these drinks. Let's say I wanted to do a round of meads at a Cordor tavern for a group about to go sailing. It'd be gone on server swap, eliminating the possibility of doing such a thing. I have not tested the other drinks to verify if the same loss occurs.