[Teodolfo]

There are plenty of free, open access journals that are reputable.

JMLR http://www.jmlr.org/ is quite successful. There are some fields, such as machine learning, that are not dominated by for-profit journals. Why is this possible in some fields and not others? My answer would be that it is possible in all fields, but incumbency advantages can be very strong and coordination across academic volunteers can be more difficult when they are individually less secure.