To be honest, I've played in both types of groups. I've played in groups where everyone died that saw us (and the bodies were taken, gotta love organlegger contacts), and I've played in groups where if someone died it was completely accidental.
I usually push it up to Professionalism, but I can see where they are coming from with some of the shows you mentioned. Chuck, Human Target, Leverage, White Collar, these are all shows about Good Guys and for the most part they don't kill people. Sure in Human Target Guerrero was the odd man out, but the rest really didn't like to kill people. I think you're players seem to have taken on the "We're the good guys hitting the corporations, and we won't sink to their level" vibe that was really strong in earlier editions of the game.
I haven't actually run Ghost Cartels, so I don't remember the job mentioned off the top of my head, but if they are insistent on sticking to their morals, don't try to break it. Just take it in stride, let it bite them in the ass (decisions always come back to bite us in the ass in SR), and possibly let them make a counter-offer.
I remember one particular run with The Guys (before they were renamed The Guys You Call When Everyone Else is Busy) were offered a job to ice a local Yakuza jazz dealer that was selling almost exclusively to school kids in the area. We turned it down, but we offered to leave him rotting in a Siberian Prison for 80% of the pay. A few calls to contacts, a bribed guard, and some minor fingerprint reconstruction and this guy was out of the picture.