[mlindner]

Your credit is not affected. Large companies do not "only pay a portion of the tax they owe". They are following the law and taking tax exemptions. You can do the same. Disagreements arise in the details of tax law in how various exemptions combine with each other, especially if you itemize deductions. You can't usually just say "I want to pay less", you have to have some reason why you think you owe less.