Do you really think YoBit concern about the quality of campaign, all they want is trouble-free campaign on Bitcointalk until their funds allotted to campaign is exhausted. Hiring Yahoo solved this problem for them and they gained little reputation to run campaign without getting any hammer from Theymos. Though, I still think current scenario is quite ok because Yahoo is doing commendable job to cut-out spammers at maximum.
Well, if there are 300 users like somebody said and it could increase, I doubt yahoo would be able to control it at a good pace. Requiring approval before you get satoshi, should prevent users who only post PoA stuff to get satoshi and withdraw. I have seen at least three users who did this and can't say there is no more. I agree with you that they don't want 'a good campaign.' See, they accept a user who doesn't post anything since months ago and suddenly posting 10-20 posts a day.
But please excuse me,I was just wondering where do you get the data? I'd love to check it myself too.
https://bitcointalk.org/index.php?topic=5188149.0