Before jumping on Trek, I would first point to whomever put the tape on the bike in the first place. I assume it was the LBS? I understand why Trek said no go if it was the LBS' fault as they caused the damage. however, they should be repairing the paint on the frame for you in that case. What type of tape did they put on it? I have done this on several of my carbon bikes with simple black vinyl tape and it has never removed the clear coat.