You might lose your job, because you are making money off of your position and it is costing the restuarent as AKA-mad4mouse pointed out. Don't risk it.
I recently had to make a large purchase ($1100) for a non-profit I volunteer for. I considered using my Disney card to make the purchase and then get reimbursed. But I am the Treasurer who signs the checks. Even though there would be a receipt showing the amount, I was worried it would look bad writing myself a check.
Believe me, I would have loved the extra $11 dollars for Disney.