I worked in a liquor store. I'll bet (since you say he's a vodka drinker) it's the airplane bottles (or 'mini's as they're called) -or- a half pint (that's the 2.75 I'll bet) of vodka.
ALso those 'power beer' drinks ....
like an energy drink with alcohol
can be on special.
There was a manager of a local foodchain restaraunt who'd come in every day and buy four mini bottles of vodka. He'd drink all four in his car before going to work.
I was a vodka drinker.
Vodka drinkers don't like to switch around.
Vodka does the job far too well
to be experimenting with anything else.
Tall beers run around 1.85 or something like that.
It's been a year or so since I worked there.
I hated that job.