Well... I suppose you could call blackhearted Einar's complete willingness to "sell out" to the Rivan at the first chance you received, or the fact that he is starting to get the feeling that he knows you are deliberately attacking his noble character. Perhaps also, the fact that Einar is deliberately twisting Colt's intentions and holding human lives over his head out of what he perceives to be petty spite. He asked for help as an equal, and received a crotch shot in return. Regardless, Colt has pretty well lost his composure a long time ago, so that is likely the rage and testosterone talking. Not all insults make sense indeed!
Bloodless however is a little bit easier and does hold definite meaning. He doesn't believe Einar to have a drop of noble blood in him. Being a nomadic hit and run character does not reflect well on him, as he finds the tactic to be cowardly, in spite of it's effectiveness. It's also a bit of a double entrende if you will, but I'll leave that one to be worked out through in-game conversation. For now I'll say this; Colt has his reasons for being a jerk that go beyond just disliking people and feels that he understands the spirits of other people far more than he actually does.
For instance, Einar had asked what Colt needed a hand with, he would have stated something along the lines of these Brigands not being afraid use human lives as collateral, so it would be necessary to secure the safety of everyone in the vicinity. Whether that is true or not, doesn't matter. He believes these brigands to be snakes and cowards preying upon the weak. Thus, they deserve no less than destruction.
Even if some of the bandits were, "Player Character Quality" he would probably still advocate to kill them because of that bias.