I am retired now, but if I was still working and forced to return to the office, rather than working from home, I would not be going out onto the streets to buy sandwiches but would continue as before, ie taking a packed lunch with me. Many people would do the same so there would be no gain, only the misery of commuting resuming, pollution going back up and loss of productivity which many have found working from home.
There has been a recent publicity drive on social media, by our city Council, to get people back to shopping in the city centre. Many arguments against this - as another poster has said, we should stop buying more and more 'stuff' we don't need; who wants to risk using public transport (and our council is very anti-car and is closing many roads to cars to force people to use the buses). And last but not least, for me personally having to wear a mask is a hot sweaty misery and therefore wild horses won't drag me into going to shops until masks aren't necessary. Should that not happen, then I'm fine with online shopping and never setting foot in a shop, coffee shop or restaurant again.