That is more likely a result of legal requirements. As a general rule any personal benefit you get counts as your income and is taxed accordingly. Expensing is not, instead counting as a business expense.
To avoid people just forming a personal company and declaring everything they spend a business expense and thus not taxed there are rules around what can be counted as a business expense.
If you instead want to take your salary in the form of Fiber One bars, but pay taxes on that spending in dollars, then your accounting department might have had fewer issues since they would not be mixing legally distinct costs and accidentally committing financial fraud.
To avoid people just forming a personal company and declaring everything they spend a business expense and thus not taxed there are rules around what can be counted as a business expense.
If you instead want to take your salary in the form of Fiber One bars, but pay taxes on that spending in dollars, then your accounting department might have had fewer issues since they would not be mixing legally distinct costs and accidentally committing financial fraud.