I would guess it is still just a supply and demand thing; however, with the online check in that I did last week, I was able to indicate that early check in was more important than the other things on my 'wish list'. So, while I asked for ground floor, near transportation, my preference for early check in trumps those requests. Sometimes our TA puts early check in requests on our bookings when she knows we have an early arrival flight.
Good luck. We are arriving at BC around 11am and would love early check in!