Originally Posted by
The Giant
Pretty much this. A human can worship Thor if he wants, certainly, but he is much more popular among the dwarves. Hel is specifically the goddess of the dishonored dead, which requires a system of honor/dishonor that really only applies to the dwarves and those humans that choose to believe in such things. If Haley died of disease, she wouldn't go to Hel because she wouldn't believe that she had been dishonored.
Also, this. The Twelve Gods are worshipped as a pantheon, by everyone, including evil characters like Kubota and Tsukiko.
As for the Oracle situation...no comment.