I have referrals there and I get money from them.
Did you know that the AVERAGE of people who click links is about 30% ? Perhaps you are one of those unlucky ones that none of your referrals click, furthermore several might be pending and then you don't earn any money either. At CAC sites you see them in your downline ( I do not know about the other sites) (Gypsydad has a CAC Script).
Hope this helps,
Have a nice day,
Pos