Sorry, I assumed that we were talking post-Covid when things are back to normal.
In the current situation, the financial support (UBI if you like) is the result of people not working. Not the cause of it. The cause of people not working is the government directive not to and the closure of shops, bars, restaurants etc. However, in the absence of those conduits for spending, demand will effectively drop as well. There's obviously still a demand for food from shops, but that is being supported by people still working food production and supply chains, so there's no supply/demand disparity there once the daft panic-buying has passed.