It is a fair question, but there have been ads from social-networking sites on Rat.Net for years. The ads that have been shown are a fraction of those that have attempted or requested to advertise here. However, that isn't different than any other business or industry group that has asked to advertise here, not all of them work out.
Of those that do end up here, some do well - others don't.
I don't pretend to understand dating sites. If my wife decides she doesn't want me around anymore I'm not sure finding a relationship would be a priority for a while