Gun,
I understand your concern, but getting upset about one manifestation of immoral behavior on a series devoted to people doing immoral things doesn't seem all that coherent to me. If I can use a crass analogy, its rather like being in a cesspool and claiming that one poo in particular is making the whole place stink.
Besides, its unfortunately part of the law of diminishing returns. The Sopranos audience has been fed a steady diet of violence, rape, killing, sadism, mutilation, lies, betrayal, adultery, nudity, perversion, fornication, foul language, and the like. If one continues to merely give them more of the same, eventually the shock value begins to wear off, they get numb, and then they get bored, and so to "shock" them some more you have to introduce something new, break yet another traditional taboo, push the envelope a little further (although there is precious little envelope left.) They only have a few cards left in the deck (cannibal gangster anyone?) but you can expect most of them to get played before the series is through.
Anyway, once the initial barriers go down and a society becomes innured to decadence, there really is no way to say "this far and no farther," suddenly introducing standards when you've blown up the entire concept becomes ludicrous (or Ludacris if we are talking musik).
- SEAGOON