But also i think it depends on management since if the gambling site owner is lousy then he cannot get profit for himself aswell as the owner of dating sites if he doesn't do some unique updates well he cannot get more users and advertisers so my point of view for this comparisson is totally depends.
I agree, this depends on how effective the marketing strategy of the owner is. We all know there are certian kinds of gimmicks than can make the audience interested. No matter what kind of site it is if their promotional and marketing people are so talented, then I can say they will most likely earn big.