As I mentioned in another thread (in "Author's"), I finally asked Lazeez directly. As we suspected, his issues were focused on authors suddenly deciding to publish and acting like asses, drawing readers away from the site.
In general, the few published authors here have been good citizens, seeing the SOL audience as an excellent sounding board and a steady source of revenue (i.e. hurting the site would lead to a loss of sales very quickly).
The biggest problem we've had so far, has been authors caught between books. They publish their old stories while leaving them on SOL, but try to sell their newest books (which Lazeez sees as a variation on 'teasers', where readers are given a couple chapters for free and are then asked to purchase the rest of the book).
The solution to that, for most of us, is you publish it first, then after a certain period, after the sales drop off (generally at the 3-month mark), we offer it for free to help boost flagging sales.
However, the end result is that Lazeez will NOT create a publishing category, as he sees it as a site endorsement of publishing as an alternative. (I'd suggested it primarily so we could off-load the publishing discussions so they wouldn't overwhelm readers/authors uninterested in the topic.)