For US taxpayers, using a simple per diem system makes a great deal of sense. Not only does it give the employee discretion in how and when they eat, but it cuts out lots of bean counting which in and of itself costs the employer money. As to the specifics, rather than worrying about whether the eggs at some property are too runny, worry more about performance and motivating people to do better, Unless the company is spending its last cash on hand, an extra egg won't break the bank. But, a poor worker may do a lot of harm.

All of this presumes an employee who is being fed to sustain him rather than an employee who is entertaining clients, prospects and others. This is where it can go off the rails.