Maddie is sitting alone at a diner when Ezra, Richard, and Jules show up in episode 1x05 “Is a Shark Good or Bad?”. The trio confronts Maddie about what she did to them and Maddie warns them to back off in episode 1x06 “The Maddie Code”. The trio calls Maddie back to the diner to tell her the truth about Patrick in episode 1x08 “In the Game”.
David is out at lunch when he sees the news about the plane crash that Marcy predicted in episode 1x02 “Protocol 6”.
Oliver, Rene, and Curtis eat lunch at Big Belly Burger while researching they new Black Canary candidate in episode 5x11 “Second Chances”.
Where Daniel and Joseph get coffee in the pilot. We briefly see Joseph standing outside here in episode 1x15 “The Dirteaters”.