Particularly beer. It’s a carbonated liquid. If anything getting the exact portion control you want would be even easier. No longer would there be temptation to round up the amount you want to drink. It would be less wasteful than bottles and more convenient than mini kegs. It would be more economical and would stay as carbonated as soda. About a third of the price of beer is the container. That math is based on looking at the cheapest bottled soda in a store.
And why not coffee? Just buy all the coffee you need at once with no steps needed. If you make iced coffee with it its going to be fine. Big coffee wants you to buy a product from them every day, because they can make more money from you. You aren’t buying your milk per drink? Why should you buy any liquid per drink or with extra packaging?
Buying anything every day is stupid. Just buy the finished product in a volume where you are taken care of for the week. It’s how you buy anything else. Products should be sold in a way where you can accomplish that with minimum packaging.
It’s valid for beer, too.