Again, you are confusing the vouchers issues by your store with the “chessed dollars” people are talking about, not one and the same.
As for the vouchers your store donated to the local organization, obviously this organization feels they distributed the vouchers to those who need it/them. If you dont like how it is used, take it up with the organization that distributes them.
Let me ask you this question. If these children are wearing $12 payless shoes to school every day, should they wear those on shabbos as well?
Lastly, the mother who used these vouchers had to get them from a tzadaka, its enough she had to swallow her pride and approach someone for help, now you dont fargin her kids the shoes? For goodness sakes, get a grip.