I think the only way these big priced players will leave Everton is if Moyes thinks the money can bring in players of higher calibre. If we sell Fellaini, we could bring in 3 average players and to me it seems like Moyes would do anything to prevent a star player from leaving. Lescott left for 24million, not because Moyes wanted the money, but Lescott practically forced the issue.
Keeping hold of star players is more important than bringing in lots of average ones year in and year out. To realistically think that any team can keep star players without playing champions league football every year is delusional. Look at Spurs, in the champions league one year, lots of ambition, spending money, bringing in great players, yet Modric wants more just one season later. It's a tough league and even if we spent loads every year and showed major ambition, these situations will still occur if we don't achieve champions league football every year.
I can't see Fellaini forcing a move and unless something ridiculous of an offer comes in, I would be surprised if Moyes even considered selling him for anything less than 30million.