Michigan (and most states) has a "USE TAX" that, technically, requires everyone to claim their out of state mail purchases on their tax return:
"Use tax on tangible personal property is similar to sales tax, but applies to purchases when Michigan sales tax is not charged. Use tax of 6 percent must be paid on the total price (including shipping and handling charges) of all taxable items brought into Michigan or purchases by mail from out-of-state retailers. It applies to purchases made in foreign countries as well as other states. Businesses registered for sales or withholding tax may remit use tax on their returns. Individuals can pay their use tax liability on their MI-1040 tax return."
Most people are either unaware of this law or are breaking the law by ignoring this rule. There has been talk of cracking down on this, but right now it is not enforced much at all. Next time someone is up on their personal pulpit claiming absolute honesty and integrity, ask them if they claimed their use tax.