The tax code is way too complex.
Every item in the tax code is there because someone in Congress, along with their lobbyists, thought it was a good idea at the time. All of the exemptions and loopholes are designed to encourage certain activity and discourage others. I know we all like our deductions for home mortgage interest and property taxes. Those deductions are there to encourage home ownership. All of the areas of the tax code affecting business taxes likewise encourage businesses to spend money or invest in certain ways, and discourage other types of business activity.
Government needs a certain amount of tax revenue from all of us to perform the essential functions of government. Maybe they should just send us all a bill, and scrap the existing code. Then businesses and individuals would make their financial decisions based on whether that activity is good for them, not based on whether there is a tax incentive to arrange their finances a certain way.
Actually, the exemptions and loopholes are designed to reward political contributions.