Is this right that you didn't keep any opportunities for the newbies. If you do not give them opportunities, how will they prove themselves what they are really capable of.
As you are already Junior Member I dont really get why you are asking this question?
But to answer your question: newbies dont have to prove themselves on bounty campaigns. They should not join the forum to participate in bounties from the first second that they are on the board. They should first accumulate some experience by reading on the board and writing comments in topics that they are interested. They will soon enough become Junior member and then can participate in bounties as well.
This is my point of view on it.