Thanks everyone for the info about this topic, I just feel unfair for those people who do this kind of thing that aim to earn a lot by any means. And now I know that having different accounts that joins different campaigns is quite allowed but it is not recommended by higher members. Also thanks for giving some tips on how to know if someone violate those rules so I can report them together with substantial and concrete evidence. I hope this might help clean up the forum and lessen the abusive members.