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.
Large beer containers are “rare” for the same reason large soda containers are rare: carbonization. If you store an opened bottle of beer for a few hours, it will go flat, killing part of the taste with it. Beer is even worse in this regard than soda. You want to finish the whole thing in one sitting for beer. Very few people consume 2 litres of beer in one sitting. … But … Every single self respecting bar has beer from the tap, right? That stuff doesn’t appear magically. It comes in kegs. You can buy those kegs from a wholesaler, or from the internet. These kegs work by inserting CO2 to pressurize it. So you will need CO2 tanks and a system to pressurize the whole thing. Not super hard to get, but not something you find in your supermarket either. But if you consume enough beer, it can absolutely be worth it to buy a tap, CO2 and kegs instead of bottles.