Aug-10-2012, 11:11 AM (UTC)
It makes sense to me. If they're living within 'normal' society, then it's much better to age as a human would, that way they can fit in and keep their secret selves, well, secret. If I remember correctly, the Twilight Cullens moved around quite regularly to avoid suspicion..ageing would prevent having to do this, though if one chose to remain at a certain age, they'd have to think about flitting at some point.
*for the night is dark and full of turnips*