Martini
There is only one respectable drink for a DM: The Martini. I mean a real martini which is just gin, a little vermouth, and an olive; nothing pretending to be a martini or ending in -tini. It is the most just as planned of all the drinks. Simply picking up a martini glass kills a little bit of your soul and lets you sink even lower into vicious disregard for your players. Other drinks promote camaraderie, however. The martini doesn't care. It doesn't fudge rolls. It doesn't give tip offs to trapped chests and cursed items. It is death-by-neutrality with an olive.