Strange. Our drivers always place items in plastic when it rains.
The worst is DHL, were 300+ yards from the road/mailbox and they put very expensive packages in the grass under mailbox instead of bringing to the house.They do the same thing at my place. Dump it beside garage when covered porch is 20 ft away.
Just did it again today and the box was ruined to the point I had to empty it and drag stuff inside.