BEFORE finally settling on Seattle as the home of Amazon.com, founder Jeff Bezos briefly considered placing it on an Indian reservation near San Francisco to avoid collecting taxes. But Mr. Bezos learned that the reservation couldn’t be used as a sales-tax haven after all so he had to look elsewhere. Offering prices free of sales tax to customers in California, the most populous state, was the goal, and that would be possible only if the company were placed elsewhere. Today, Amazon manages to collect sales tax in only five states, which gives it a continuous advantage over companies who have to collect them in all or most states. And competitors aren’t the only ones damaged by Amazon’s stance on sales taxes. Such a stance also means the loss of considerable revenue to states and localities that... --..