All three cases (and more) happen -- and anybody that believes it ain't so, or that "being cozy" (which can make or break careers worth of millions) is of less concern than direct bribe, probably also believes in the tooth fairy.

Among countless cases, some uncovered, some unknown: http://www.nytimes.com/2006/09/09/washington/09cuba.html

It's no new either: https://en.wikipedia.org/wiki/Operation_Mockingbird

And not just in news either: https://topdocumentaryfilms.com/hollywood-and-the-pentagon/