moz has said that he thinks tattoos are cool, but wouldnt get one because he is wimpy, if you will. he says he cant think of something that he'd like to have on his body permanently. additionally, i think he said he didnt like pain.
as for the scars, moz had (has?) a fascination with boxers. he has always toyed with violent imagery - SATH, rusholme ruffians, spring-heeled jim, national front disco, etc. i can only guess the scars reflect that fascination.
i happen to like the fake scars. they look particularly sexy in the boy racer video. yummy! scars give a person such personality.