If the Western Australian Cricket Association was short-sighted enough to say "Nope, we're staying here" CA would give them the shit dates every year until they buckled.
Then Nine will step in and force CA to give Perth good dates for the test. They couldnt give a damn where their only prime time test is. The WACA test is very early this year, 13 November, and is actually the second test on the calender, overtaking Adelaide. Little doubt that was from Nine's pressure considering they want Perth to replace Brisbane as the first test of the summer.