1. They're omitted because they're NPCs, and because Denarians with Coins are all hypothetical stat blocks anyway. They should definitely have them if they possess and use magic.
2. Depends on the item, and how direct it is. A Warden's Sword clearly doesn't, and any offensive magic on it just makes the sword sharper (a very indirect way to cause death), while Harry's rings likely would, as he has to will the power to leave the ring directly (a much more direct thing). It's about using your focused will to kill someone. If you're doing that, you get Lawbreaker, if you're not you don't.
JustinS: I disagree completely on the relation between Sponsored Magic and Lawbreaking. Once bestowed, the magic is a part of the user and requires the same effort of pure belief and will to use, and it's that effort that taints murderers with Lawbreaker. There is also no meaningful thematic distinction between using raw sponsored magic and channeling it through your existing magical prowess, and so the two should not be notably differnt mechanically either.
Any other ruling leaves anyone with Sponsored Magic with the ability to casually break the Laws, and that's completely unacceptable thematically, as well as disagreeing with what we've seen in the books (Harry was never any more detached when using Hellfire or Soulfire than using other magic, just for example) and is also blatantly unfair mechanically as it allows someone with a -4 Refresh power to be allowed vastly more options than someone with -6.