Hhampuz and yahoo have monopoly here not because they are threatening other campaign managers and participants, but simply because they are providing best quality services.
There is no monopoly here. Thye are just providing a good service, they are here for a longer time, have more contacts, so people here them more.
I am participating for more than an year in a campaign not managed by any of them, which is paying more than most out there.
There are also campaigns managed by Coolcryptovalor, Darkstar_.... there are others that come just to make a few ones and disappear.