Its literally 2 actions to load a container with water, and only one for magazines, one for guns, one for flashlights. In my opinion at least, a big part of the game is supply management. Intimately making sure you have enough food and water to last the day, enough ammunition to get more food while fending off hordes, enough batteries to make it through one more night. This is especially apparent in the early game where you have to struggle to get anything. Later i get how it can be tedious but for the most part you will only have a couple tools that require batteries, each of which can be modded to charge via ups, or otherwise have their capacity expanded, 2-4 spare magazines on hand for 2-4 guns, assuming you're using guns at all, and 1 primary water container with maybe a couple secondary containers for broth or something, each of which is simple to fill with whatever it is you want with 1-3 actions per container. Having all these things can require a tedious amount of attention and work, but it makes it so you have to actually manage your time, because in the end, you have a finite amount of light, of night, of food, of water, of ammo, of supplies, and above a finite amount of time before something kills you.