Scientists Anguish

How is it through history, with even very noted scientists, that they cannot gain credence based on their own endeavors and works, but have to rely first on gaining  favor and/or support of other members of society like royalty, or defense contracts for their works to have established noteworthiness?

This situation appears so prevalent, as in cases with John von Neumann, Albert Einstein, John Bell, Neils Tyson, Lawrence M. Krauss, Carl Sagan, Robert Oppenheimer, Christopher Columbus, Tycho Brahe to mention but a few. How can science advance unhindered this way?

Note: the material herein is not necessarily a reflection of entropy of current societies.