1
general::
Come and eat, the meal is ready, as in She called to the children, "Come and get it!" Originating in the British armed forces, this term passed to other English-speaking armies in the late 1800s and was taken up as a dinner summons by various groups who shared meals in a camp, among them cowboys, lumbermen, and construction workers. It occasionally is used facetiously for other summons, especially for sexual favors. For example, "‘Come and get it,' she said and going to the bed, she lay down . . . and beckoned to him" (James Hadley Chase, You're Dead without Money, 1972).
American Heritage Idioms
2
general::
Phrase(s): Come and get it! [and] Come ’n’ get it!
Dinner’s ready. Come eat! • The camp cook shouted, "Time to eat! Come and get it!"
McGrawhill's American Idioms And Phrasal Verbs