People working from home had the potential to save a lot of money (bar perhaps higher electricity/heating costs, which will still be a load less than a Starbucks on the way in, Pret for lunch and possibly another drink after work).
I wonder if those who do go back on a (semi)regular basis will quickly get back into the habit of spending £5-20 a day on food and drink? Perhaps people will start with a packed lunch and best intentions and quickly revert to laziness and convenience...
It's no wonder Boris and others want people back in town to protect these huge chains.