I work for one of those companies make them fly Y regularly. However I fly most of my personal leisure in J, either paid, or upgrade using points or award booking.

I can recall once on a KA flight, me and my wife couldn't sit together in J as we booked separated, didn't do olci and we arrived the airport very late, they actually opened up the F section just for two of us. Doubt they would do it for non status J pax.