Apart from making him look less like the cartoon character he's wanting to dress up as?

You know dressing up as a cartoon character doesn't actually mean you have to live as that character for your entire life, right? This was just for an afternoon out?

Are all the cosplaying teens painting themselves blue to look like Na'vi closeted misanthropes, deeply scarred by Hollywood in such a way that's left them wanting to go outside looking like aliens?

Sometimes kids are just being kids.