I am offended by the daughter's attempt to use Remembrance Day as an excuse to rant against a store she obviously doesn't like with the requisite anti-American quip thrown in for good measure.

The situation really has little to do with whether dad was a vet or not.  The fact that the incident happened when you went shopping at 10 AM on Remembrance Day suggests at a bare minimum poor planning on your part.  Who goes to a store the size of Costco with an elderly parent with the idea of being home by 11?

Anyone familiar with Costco understands their restrictive payment structures i.e.  Cash, Debit, or Mastercard.  Not to mention that you cannot enter the store unless accompanied by a member, who technically is required to make the purchase.   

Admittedly, the cashier and manager in question handled the situation poorly.  Not because of sacrifices made in the war, but rather the need for some goodwill towards an elderly customer.  But this is hardly a case of Costco disrespecting vets.