The fact that you have paid tax in all its various forms, and national insurance and would be happy to receive vouchers for help seems strange to me. Did you pay your tax in vouchers? Would HMRC accept vouchers? Then why should anyone else? And having paid a lot of tax over the years you would be happy to have very little to spend when really someone should be receiving enough money to live on with dignity and have nothing to be ashamed of. After all, that person has contributed to the system as has everyone else. It doesn't need to be a lot of money but enough to pay bills, buy food for the family, heat the home and not have to use foodbanks.
Giving someone a debit card seems a good idea on the surface but what if the person does not have a bank account? If they are homeless what do they do for proof of address? Proof of identity? Who would open that account? How much would that account cost to run and who pays for it? Banks are businesses not charities. What is to stop the card holder buying his/her food then selling it for drugs/alcohol. What then would have been achieved? I'll tell you what- nothing, absolutely nothing, zilch, nowt. But there would be an increase in the cost of bureaucracy.