We shipped a box with toiletries and baby supplies (diaper, wipes, etc.) to the Grand Floridian in September and the Contemporary in last month. We used Fedex both times.
You might want to ask this on the budget board or call the resort. I could swear I read on the budget board that the resorts were starting to charge you when you have packages shipped before your arrival.
much faster and less hassle at the airports. calling the resort for info sounds best. hope they dont say no just because its a moderate. i called the other day to get a map sent to me and they said no. i mentioned that the WL did and their reply was " their a deluxe resort ,we are not". so i offered to pay them , she still said no. ( POR)