Is that all they spend it on? Rent, mortgages, caring for family members?
There are people (not me) who say that people are using food banks who also spend money on less essential things like holidays, cigarettes, cars, alcohol, takeaways, mobile phones, TV, etc etc etc. Wouldn't it be a good idea to disprove it rather than just shout down the questioner?
(And I'm not at all sure that food bank users are all good budgeters. We hear far too much about parents who can't afford to buy breakfast for their children and so schools need to have breakfast clubs. Bearing in mind that a breakfast of porridge, or toast and jam, can be had for £1 per week, it isn't just budgeting that's the problem.)