Why is the term Beer plural? ie, I had a couple of beers last night, but the animal deer is not. I saw 2 deer?

I think you had a couple of beers just now......Why is the term Beer plural? ie, I had a couple of beers last night, but the animal deer is not. I saw 2 deer?
why is beer plural thats because of the word bearWhy is the term Beer plural? ie, I had a couple of beers last night, but the animal deer is not. I saw 2 deer?
Because that's how the language developed. It's not for us puny mortals to question pluralization and spelling.
The term Beer is like deer the correct statement is you had a couple of beer last night however most people who have a couple of beer usually says beers but it is incorrect