> Don't you have receipts and turn them in with an expense report?

Yes, but ...

I'm supposed to charge ALL meals to the corp credit card. I am required to report them
on my expense report as NON-reimbursable. Then, I am to claim/expense only the daily
per-diem.

The NON-reimbursable gambit is how the employer shakes-down, errr, collects the
rebate from the contract restaurant(s).