From Seattle Times Article...."If the Sonics didn't play the last two years under their lease you would have at least 41 days of amelioration of the Mercer mess, wouldn't you?" Keller asked.
This in reference to the fact that the games at Key Arena creates traffic around the surrounding area, and if the Sonics weren't in town then there wouldn't be that issue to deal with anymore! Boy, Clay Bennett and his cronies are even more desperate than I thought lol.