Explain why some argue that income tax loopholes primarily benefit the rich

Since the personal income tax is progressive, the wealthy pay a higher marginal tax rate than do the poor. If the rich can find a way to reduce taxable income by a dollar, they reduce their tax bill by more than would be true for a lower income person. Municipal bond interest is tax-free, which saves the wealthy person who holds municipal bonds more in taxes than the poor who cannot afford municipal bonds. Housing expenses are tax deductible, which results in a larger tax saving for those who can afford to own their own homes.