A drink available at Boot Liquor. Its name is a portmanteau of science fiction author Alan Dean Foster and Australian beer Foster's Draft Ale.
One of Foster's works is The Dig, which was adapted into a graphic adventure game published by Sierra rival LucasArts only a few months after Space Quest 6 was released. Whether this is a coincidence is unknown.
The labels are described as being hard to read because they are so faint, and that they must have been printed in draft mode. This refers to a function of computer printers where a document is printed using a small amount of ink in order to test the cartridge.