I grew up in Alaska anyway, and my mother was paid monthly, so we typically bought all our supplies for the month at one large volume shopping trip.
We used the 2 quart size (rectangular) waxed cardboard type packaging. The freezing will make it swell a bit, so don't know by personal experience if gallon plastic jugs have enough expansion space. After it thaws, shake well and you might periodically shake before pouring. The freezing interferes some with the homogenization (the balancing of the fat particles) and so you do get some cream rising to the top.
edit: If you have a Dollar store near you, the shelf stable milk cartons are great to have in the pantry. Don't know about drinking it, but it's fine in my coffee
Shelf stable milk was introduced back in the 70s, and while I was leary at first am fine with it now.