(1)(a) Except as provided otherwise in this subsection, no gas company, electrical company, wastewater company, or water company may charge, demand, collect or receive a greater or less or different compensation for any service rendered or to be rendered than the rates and charges applicable to such service as specified in its schedule filed and in effect at the time, nor may any such company directly or indirectly refund or remit in any manner or by any device any portion of the rates or charges so specified, or furnish its product at free or reduced rates except to its employees and their families, and its officers, attorneys, and agents; to hospitals, charitable and eleemosynary institutions and persons engaged in charitable and eleemosynary work; to indigent and destitute persons; to national homes or state homes for disabled volunteer soldiers and soldiers' and sailors' homes.
For the purposes of this subsection (1):
(i) "Employees" includes furloughed, pensioned and superannuated employees, persons who have become disabled or infirm in the service of any such company; and
(ii) "Families" includes the families of those persons named in this proviso, the families of persons killed or dying in the service, also the families of persons killed, and the surviving spouse prior to remarriage, and the minor children during minority of persons who died while in the service of any of the companies named in this subsection (1).
(b) Water companies may furnish free or at reduced rates water for the use of the state, or for any project in which the state is interested.
(c) Gas companies, electrical companies, wastewater companies, and water companies may charge the defendant for treble damages awarded in lawsuits successfully litigated under RCW
80.28.240.
(2) No gas company, electrical company, wastewater company, or water company may extend to any person or corporation any form of contract or agreement or any rule or regulation or any privilege or facility except such as are regularly and uniformly extended to all persons and corporations under like circumstances.