If you include affiliate codes as part of tracking codes, I can definitely see some users wanting to keep that data preserved. For instance, someone may want t

If you include affiliate codes as part of tracking codes, I can definitely see some users wanting to keep that data preserved. For instance, someone may want to reward some shareware author with their amazon purchases. Social organizations like churches, clubs, etc. might encourage their members to tack on an affiliate code to keep them funded. It's hard to see the use case for keeping the utm_* tags, but not all tracking codes are meaningless to an end user.