“Never use milk jugs to store water. As I’ve heard.”
True. You can’t get the milk smell out plus they are very thin and you will have water on the floor within a short time.
Perhaps, but they are unbeatable frozen. Frozen jugs of fresh water will extend the time it takes for a fridge to ‘lose its cool’ in an extended power outage AND provide fresh water should it take longer than you think.
I use them all the time for BSA outings. Stick one in a cooler and it will last almost a week - keeping things cool.