It would appear they don't even seek accreditation. Based on the description of accreditation given by the BBB, some people may take this to mean that Valve does not have "a commitment to make a good faith effort to resolve any consumer complaints". Either that or they are just unwilling to pay the fee. Either way... this is a pretty horrible thing for a company of Valve's size.
I've seen a lot of other discussions on here lately about people having bad experiences with Steam Support. In the interest of acting and not simply talking, how would you guys feel about starting a petition with the intent to motivate Valve to improve the quality of their customer service? Is that something other Steam users are interested in? Has this already been attempted?