I love depato (department store)! In Japan, depato are multiple stories tall (7-12), and feature a supa スーパ (supermarket) in the basement. These are called depachika (literally under the depato) are they are AWESOME!
Uncountable numbers of glass counters with any kind of food imaginable. Pictured is of a panya ("bread store") and a traditional japanese sweet (wagashi 和がし）counter which sells things like mochi and daifuku (made from glutinous rice).
Depachika are really convenient because they are on most everyone's commuting path as they go home. Most Japanese do their grocery shopping daily at such locations, carrying the day's groceries on the train. This makes the depachika really crowded between the hours of 5-7pm, and merchants discount items after 7pm (a good time to pick up cheap sushi or strawberries!).
Connected to the supa (supermarket) area, there is usually a section selling bento (lunch boxes). You can buy just about anything in a take out box: sandwiches, quiche, bread, sushi, donburi, tempura (not recommended, fried foods are gross when they have sat out for a while), yakiniku (grilled meats), and katsudon (a certain kind of breading on meat), just to name a few.