I honestly don't know...
I am out of house (work related) 6am-6pm most days & DH does most the shopping, so I've lost track. We hugely dislike online shopping for groceries.
All day Saturday in little shops, & any time Sunday seem always busy.
I guess like 2am is still quiet if you have a 24hr supermarket nearby. My supermarkets are 8am-9pm type hours, though. Any market day is busy in the little shops.
What is your experience -- when is it quiet?