I put birre, knowing that the sentence was relating to multiple people. Is it just referring to beer as an encompassing entity with regards to what they're drinking?
Given the lack of article, I'd say it's because "birra" is being treated like an uncountable mass noun.
I think it would be singular because each person in 'they' is drinking one beer....
Yeah, without an article it would have to refer to the mass noun "beer", as in the liquid itself (rather than a particular container of beer).
Italian does this the reverse of English.
They drink beer = Bevono la birra
They drink the beer = Bevono birra
Is here a spanish speaker who just understand why we call it 'birra' sometimes? Not everywhere. It is kind cool to know where it comes from. :)
Should be, report it.
That is, as long as you typed "You drink beer" and not "You (pl formal) drink beer".