Most places have limitations of some sort on 4th of July fireworks, but outright bans are relatively uncommon. Spokane, and communities around it, have had such a ban for 17 years.
From a city release: "Fireworks-related fires in the City of Spokane dropped from 1,044 in the 10 years prior to the ban to just 46 in the 10 years after the ban. In a similar manner, fireworks-caused injuries dropped from 290 to 37. In 2008, no injuries from fireworks were reported in the City of Spokane; there were five small grass fires. Clearly, most people are honoring the ban. Violations of the ban can be reported to Crime Check at 456-2233."
And: "The Colville Tribe lost over $15 million in timber on July 4, 2003, after someone lit a bottle rocket from a boat on Lake Roosevelt. In 2006, about $6 million in damage to schools in Washington State was caused by fireworks."
Odds are, most northwesterners still are unlikely to want to go there. But food for some thought anyway.