Also, I thought shaving his head like that would attract more attention than just having that bald spot. He could easily explain that (zombies), but he's going to have a slightly more difficult time explaining his shaved head (unless he claims he did it for vanity reasons or whatever). I'm sure shaving his head was some kind of visual indicator for the direction Shane is heading, but it didn't make much sense in my eyes for practical reasons.
The bald spot is a constant reminder of what Shane did. Shaving his head gets rid of that reminder and MIGHT make it easier to live with.