[quote=@Fetzen]
Unless there are some additional unknown variables caused by elvish blood that add some degree of auto-maintenance to his skin.
[/quote]

Wouldn't surprise me. You see how Aragorn gets so filthy in The Battle for Helms Deep? Quite the contrast to goldilocks Legolas who seems to be positively glowing throughout.

To be honest, that would be really handy to an adventurer, with the heavy travelling and often dank environments they find themselves in