I've heard that argument, but I just don't see it. Are people afraid that a tournament would suddenly turn the college football regular season into NCAA basketball? Playoffs or no, there's a huge difference between 30ish regular season games and 11, just as there's a huge difference between an 8-team tournament and a 68-team tournament -- those differences would not go away. One win or loss could STILL make or break a team's season, but the final outcome wouldn't depend quite as heavily on favorable scheduling or preseason rankings.
To make the regular season more important to schools, you could still go with the bye for the first 4 teams, then in round two those first four teams can get a home game with all the money going to them
A really interesting piece on how the selection process for 4-team playoff might have looked this year: http://sportsillustrated.cnn.com/20...l-playoff-mock-selection-committee/index.html