Break time

The dining area of Agarwal Bhavan in Sowcarpet is too far away - by a few streets - from this doorway for this to be a backdoor entry. The only other explanation is that this is the main storehouse for provisions needed by the eatery, which accounts for the milk can and the boxes.

Quite likely that it is also the rest area - maybe even the living quarters - for staff of Agarwal Bhavan, who seem to be enjoying their break. Once they go to the restaurant, there is little chance of them enjoying free time until the crowd thins out!