Any city which imposes a license fee or tax upon the business activity of engaging in the telephone business, as defined in RCW 82.16.010, which is measured by gross receipts or gross income from the business shall impose the tax at a uniform rate on all persons engaged in the telephone business in the city.
This section does not apply to the providing of competitive telephone service as defined in RCW 82.04.065 or to the providing of payphone service as defined in RCW 35.21.710.