Roddenberry made most of his living for a number of years on the college speakers' circuit. I saw him several times. I think it was during that time when he honed the personna that he'd present to fandom for the next several decades by enlarging on the image he and Whitfield created in The Making Of Star Trek:
the idealist, the skeptical and independent thinker rebelling against the mediocrity of corporate groupthink in Hollywood and defying authority. His sure-fire applause lines included stuff like "I believe that all of you are much smarter than the executives in the studio boardrooms."
You can imagine that was just tailored for the college crowd in '72, '73, '74...basically, GR got good at flattering the audiences who paid his bills.