Why don't you want to take the deduction?
Generally, you are expected to deduct your ordinary and necessary expenses. If you skip the expenses so you can show a higher income to qualify for some tax credit (like the child tax credit, EITC, or IRA contributions) that can be tax fraud. And if inflating your income does not change your tax, it could still be bank fraud.
Story time: A person I know is a delivery driver, and was applying for a mortgage. The bank said his income was too low -- let's say he grossed $40,000 and had $20,000 worth of mileage, showing net income of $20,000. Even though the mileage deduction improved his cash flow, the bank was (stupidly in my opinion) looking at the net income. If this person decided to file, leaving the mileage off his return to show a "higher" income, it would not necessarily be tax fraud, but it could be mortgage fraud. So he smartly found another bank that was willing to work with him.
