I have heard that its because of interest of large stake holders, and only those get funded, who have some kind of association with them ?
Not sure where you "heard" that, but it's utter BS. I'm one of the largest stakeholders, and I don't have an association with any of the currently funded projects. The only DHF project that BlockTrades (or me personally) received any funding for was the image server proposal (50K HBD). There was also a 3K proposal by @therealwolf to create FontAwesome icons for Hive, but I only acted as a payment agent for that, I didn't keep funds associated with it.
Why blocktrades don't work?