the money is already set aside by the gov'mt for what's included in vouchers whether they're redeemed or not. so, if she doesn't use some/all of the vouchers, that money will get put back in as gov'mt surplus and end up sitting there for a long time until eventually it gets reappropriated in the form of a grant or loan.
kudos to you for not getting the food and then selling it on craigslist or something. that's what many people do. sigh.