I saw this same "problem" in many of the comics I bought from a regular Joe seller. Very noticeable on the issues with black covers. As a later poster said, they all look "trimmed" but it's just how the comic came out.
I haven't submitted one for grading yet, so I can't be 100% positive, but from what I've read/seen, it shouldn't hurt the grade. I suppose CGC would consider this along the lines of a production error.
-- Dave
Should not affect grade. I have had similar issues with different books (came back 9.8).
Ryan (thumbs u