It's obvious that this does get abused by some sellers. It's also obvious that states don't have the authority to enforce their sales tax law on out-of-state s

It's obvious that this does get abused by some sellers. It's also obvious that states don't have the authority to enforce their sales tax law on out-of-state sellers. Their options are either to switch to a tax structure that they are capable of enforcing or to lobby the federal government to regulate the collection of sales tax by out-of-state sellers.