My idea wasnt anything like that. It was simply that basic general foodstuffs like generic bread, pasta, rice etc should be free for the poor and could be regulated with a card or some sort of system like that. Middle class and up wouldnt have to bother with it, they c an continue to buy their usual stuff and if the program is a succes, maybe expand it so that middle class etc can buy this kind of stuff if they want.
Future expansions could include adding more stuff to the "free list" like generic eggs, fresh produce etc. It wouldnt really cost any money because the government can make this kind of stuff much much cheaper by buying in bulk, removing certain taxes etc, and then considering the poor no longer have to buy bread and such, their centrelinks can get reduced by an equivelent amount.
Net cost for this program would be zero at worst, if anything the government is likely to SAVE a considerable amount of money whilst providing a guaranteed and unalienable supply of basic food for the poor and needy. At the very least a program of this type should be trialled with a small sample of centrelink users, considering it would cost the government very little to do.