Hear, hear.

Anyway, being forced by the realities of the situation, and his own family members' idiotic alignment with the vampires, to cooperate with the lesser evils (even Damon: it's not like John gives him a pass while hunting down much nicer or more harmless vampires - he's no Holtz from "Angel", for instance, who proved more than once that he was indifferent to the morality of any situation and cared more for revenge than righting a wrong) does not make him a hypocrite or 'ends justify the means' (did you reverse it on purpose? If so, I don't get your meaning) pragmatist.

Someone who abused Ends Justify the Means morality would, for example, burn down a building full of innocent humans to kill a vampire inside, or perform a ritual to kill a large number of vampires that required a human sacrifice. John does not do anything like that. Offering help to the Salvatores to protect his daughter is simply setting priorities: first stop the vampires threatening your family, and if you can use a weaker vampire to take down a more powerful one, that is perfectly morally acceptable (unless you are enabling him to get that power himself and become a greater menace to innocents, or are letting him kill innocents in order to empower himself to fight the greater menace - those are cases of Ends Justify the Means being abused).