basically having killable merchants gives griefers a chance to basically tank the player crafting economy (which doesent affect them in the slightest becuase they're either 1chr pvp builds or suicide bombers) so they dont give a shit.
I have 3 CH.
I'm not power build.
I don't have suicidal bomber alt anymore.
I'm crafter.
I doing alot caps everyday with my magic cartriges.
So I trading.
But... I killing Sha Enin, banker and other traders at NCR, yes. Because I never liked this city, even at Fallout 2. I doing it only for fun, to come to NCR later and say "Who killed Sha Enin??!?!?!", "And a banker??!!", "And Buster??!!?!", "Who's that bastard??", it's fun really, you should to try.
Btw going to NCR for trade... you should thank me that I killing traders there, so you'll save your stuff.
You have more chance survive if you come to New Reno with 60 HP and BA, then shout there "HEY! I HAVE ONLY 60 HP AND BA!!!!11 KILL ME!!!", then run over all locations at New Reno, you'll have more % to not die, then if you come to NCR and won't shout anything, just come there... Sometimes you can die there even without any items...