I keep my receipts, so I can answer questions like this. In April, I paid $3.14 for a half gallon at the Screen Door on the BW (BWV is our home resort): $3.69 - 20%DVC discount of 0.74 + 0.19 tax. The cast member asked to see DVC-Y on my phone to apply the discount.
I didn’t notice any gallon containers, but only really needed a half for my cold cereal most mornings of our 7-night stay, so I was’t really looking for anything larger.
Wow after all these years I never knew they had this. Staying next month for three days at BWV and the delivery is cheaper than Garden Grocers. Thanks for the heads up.
Another thing to consider: there is a Speedway gas station just across the street from the Boardwalk resort. I know they have things like pop and gatorade and powerade, but not sure if they have milk. It might be less expensive over there, if they have it. I know the powerade is considerably cheaper there than it is on-site.