Author column is shown even if the post type doesn't support it
|Reported by:||nacin||Owned by:||scribu|
|Component:||Posts, Post Types||Keywords:|
Generally the post_type_supports arguments haven't gone much deeper than the UI level, but in this case, it's very much UI. If the post type doesn't support author, then the column shouldn't show, as we're not showing the meta box, or anything in quick/bulk edit either.