Violation of RCW 19.56.020 is a matter affecting the public interest for the purpose of applying chapter 19.86 RCW. Failure to comply with this chapter is not reasonable in relation to the development and preservation of business. A violation of RCW 19.56.020 constitutes an unfair or deceptive act or practice in trade or commerce for the purposes of applying chapter 19.86 RCW.