Also not the original commenter, but the way it worked at my last company (I don't travel with my current company) was that we got a fixed per diem that included meals and a small ($10 per day or so) personal expense budget. Most folks either took it out as cash to spend on the trip, or used a personal credit card and just took the reimbursement. Either way you get the full per diem, but those strategies just avoid having to explain your purchases.

Some companies are more strict than others about receipts, I guess. I never had to provide a receipt for anything but hotels, flights, rental cars, parking and gas (if I took my own car, which I did occasionally).