I am going to HKG in late June from TPA and would like to try new airlines (Korean Air, China Eastern, for example). However, I've noticed that if the flight (DL codeshare) is operated by Korean Air or China Eastern (for example from LAX or JFK), DL only offers only B,M or Y fares, which brings the total fare up to $5K. For comparison, if I fly only on DL, the fare is ~$2K. Does Delta do it for purpose? I've tried different dates and never saw LUT or other lowest fares on codeshares.