The process of stealing Arby's (hinting roast beef) food by running through the Drive-Thru. When your friend is at the window about to get his food you run up and steal it and run away. This causes a commotion and you get double the food. Original Roast Beef Theives are located somewhere in the South End of Louisville where this process began.
PERSON 1 "What are you doing tonite?"
PERSON 2 "I dunno you wanna call Ms. B and do a R.B.T."