I wonder if dead horses know that they are being beaten again? Because this poor dead horse surely gets beaten regularly.

Unless OP has some evidence that UA & DL representatives held some secret conspiratorial meeting to plot prices for the lucrative SEA-OTP market, this is nothing more than software-based price-matching.

Worse, OP didn't do his homework. Neither UA nor DL serves OP. So, even if they have conspired, they are paying over the bulk of the revenue to LH, KL or AF.