Lopez was signed to DKP, the others were not. Unifications and cross promotions are extremely rare and only went to the headline fighters, not support guys on King cards. What was his biggest payday, 50K? King is not stupid with his money and did not see any sort of fiscal payback for those matches. And he certainly is not going to pay the opposition 10x more. As a result, we the fans do not get fights made. We do see softie title defenses. And it isn't just DKP doing this stuff.