Comcast storing WiFi passwords in cleartext?

Hi NANOG, Here's an issue raised today: https://security.stackexchange.com/questions/207895/how-does-comcast-know-my... Apparently there's a concern with customers that their seemingly private passphrases, entered in their own boxes, are being shared with the upstream ISP without an explicit customer consent, and are kept in the ISP database for an unspecified period of time. Is it there by design? if so, then maybe some tweaks are necessary? -- Töma