Hi Marisa, Thank you very much! If you're referring to the milk vending machine in Athens, I haven't tried it out myself since I don't drink milk. It's an independent 'station' (like a gas station) with a few machines only for milk. But the same structure can easily be transferred to a corner shop or a shopping mall.
First of all, the way to transport the milk from farm to seller is the same: by a refrigerated truck. It's just instead of small plastic bottles, the milk is stored in large metal trunk. As for the vending machine, there should be a refrigerator inside to keep the milk cool. Basically, the technology is ready. We need to start a campaign to promote this BYOB habit.
I think it is possible to dispense soft drinks in the way that you mentioned. But maybe it's easier to to just put a big tank of ready-to-drink drinks. We need to contact the vending machine maker to confirm.
As for which cases, it depends on the liquid. For milk vending machine, it can help with case 2-- bottle caps and tear-offs.