One thing I know about Marshall....At least when they were in the MAC they tried to schedule the toughest schedule they could most seasons. Sometimes the teams they play turn out not be as strong as was thought at the time of scheduling and more often than that BCS schools refuse to play them, especially in Huntington.
The only thing more they could do is schedule all their non-conf games away from home but that wouldn't be fair to the team, season ticket holders, concessionaies, etc...
Marshall has a good program and your right, they will play anyone. My comments were meant to show why the Herd didn't and shouldn't have made the BCS that year. They very well could have been good enough but their schedule didn't show it.
Mid majors are at a disadvantage when it comes to scheduling games. The programs they want to play aren't going to go to Huntington because the money isn't good enough. The only way to get them to do it is with systematic scheduling where the big time programs have no choice but to play them at home at least once a year. So you are correct.