Receipt reimbursement systems in companies are much more complicated than simply giving employees a hard per diem. In this case, OP was working on an off-site short-term project (that in reality lasted about a year) in Singapore, and he was allocated $60 per day for food expenses. On average though, OP was actually spending about half that amount. As the project went on, the customer's client began raising some issues, and OP was told to take the client out for dinner and some drinks. His manag…