This is a reference to the song "Post To Be" by Omarion. In the song, Jhene Aiko refers to her booty as groceries. It is a sex term. He eats food and he figuratively eats her ass in a sexualway. It is now a pop culture reference. Instead of ass, one says groceries. Only in a sexual context.
"Might let your boy chauffeur me,
But he got to eat the booty like groceries." -Jhene Aiko
1.)-prep. phrase- a polite, and usually deceptive, manner a man has to say that he is busy masturbating to orgasm.
Usually used in the presence of young children and/or parents/grand parents where one doesn't want to use the more obscene terminology, or otherwise wants to fly below the radar.
1. I'll talk to you after I finish Unloading the groceries. 2. I'm going to go unload the groceries.