NPR is on the record [0] as not even informing their editorial staff of their 175+ sponsors, which causes other issues (for which there is actual evidence, which, while reasonable, I haven't seen for your theory):

> That lack of awareness has led to some embarrassments in the past. Online spots from America's Natural Gas Alliance once ran next to a series on fracking, for example.

[0] https://www.npr.org/sections/publiceditor/2012/03/16/1487788...