1. The people that register don't search the web for reviews, but instead are simply persuaded by trustworthy-looking TV/newspaper-ads. 2. Negative word-of-mouth in this business is not strong enough: people seldom like to tell their friends they're on a datingsite. Let alone telling the about one that has succeeded in ripping them off financially. 3. Affiliate marketing ensures that sites with the highest commissions (the ones that are able to charge/ripoff their users the most) will be recommended the most on various review/overview-sites.
So, the question is: what can be done about this?