As they are effectively a catering business handling passengers from multiple carriers operating different eligibility requirements and computer systems (plus perhaps CC members and pay on the door customers), I doubt they are particularly interested in your travel arrangements, if they have access to them. It most likely really is about having the physical chit to claim reimbursement against, similar to a meal voucher you might receive during a delay and redeem at any other outlet. Much of the world still works like this. It's not right or wrong, just different to what you hoped for