So reddit faked their early users... even though they had pg's readers. A new social site must get really creative if they consider faking users not ethical (as I do).
For us, there didn't appear to be a major ethical dilemma. We used these accounts simply so that new users would see a front page of links instead of a blank website (or one with only submissions from 'kn0thing' and 'spez'). For a site like reddit, it seemed to be a key part of showing new users how the site worked. Once we got traffic (from places like YC and PG) we stopped needing these accounts and thus stopped using them.