"I would like a beer", when they meant, "I would like a glass of beer." Is it acceptable in written English?
Yes, written and spoken. It would be most unusual to hear someone ask for 'a glass of beer'!
Also, "I would like a beer" sounds rather odd.
"I feel like a beer/I need a pint!" are more usual in Britain.
and when ordering in a bar
"I'll have a pint of (name of beer)"
When in someone's home and asked, "What would you like to drink?"
the reply might be, "I'll have (a) beer, thanks."
Since beer drinkers (like many Scotch drinkers) have a favourite, it would be unlikely to order 'a beer' - they would ask for the beer by name:
"I'll have a Bud (Budweisser)/Stella/Tennant's Special, thanks."
At a bar in a theatre at intermission, it may not be possible to be too choosey, since they may not have a great range of drinks as in a regular bar. Someone ordering might say:
"Two beers, thanks."
It is more likely, if ordering drinks at a table from a waitress, that she would repeat the order back, to make sure she has it correctly, saying :
"So that's two Scotch on the rocks, two beer, one Bicardi and coke, and one OJ (orange juice)" - this is kind of short for 'two orders of beer, one order of Bicardi...
There are other variations on this - and Americans will have their own way of expressing it!
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