eh, even with Zaeed's the choice is pretty ambiguous in moral terms. Vido's a killer, after all. Pragmatically, it is far more important to gain Zaeed's loyalty and ensure his effectiveness as a team member anyway.
Plus I think that paragon persuasion cop-out that keeps his loyalty is really lame.
I don't think it's a copout.. Zaeed is on a team now, and bigger things are at stake. He's not stupid, once you point that out to him. His character is all about harsh life in the Terminus, as a lone human.... and what measures he's taken to stay alive. Paragon is just letting him know he doesn't have to do that anymore.
And the other thing is... Zaeed's got all of these stories about killing Krogan, Batarians, and Turians... but he's sinking to a deeper level by letting innocent human workers die for his own ambitions. He's gone beyond mere survival and becoming exactly the thing he hated. And Shepard will be worse off for it too. Why even bother caring about Collectors abducting colonists, when you yourself will let some workers burn in a fire... just to hunt down some merc. lol. The whole theme of the game is "Fight for the lost" and here we are being douchebags ourselves. Those workers probably already live off crappy wages as it is and already have a rough life in the Terminus. And now you would be making it worse by helping Zaeed.
Just saying. 