Are the adjunct professors trying for experience or just hoping for full professor positions? It seems to me there are plenty of small colleges and junior colleges who might need instructors.
I have some friends who are adjuncts at local community colleges. They do it for two reasons: they are trying to make some money and experience while waiting for a tenure track position to open up at some college/university, if ever; and they are damn thrilled to be working in their field at all. They have told me stories about hundreds of PhDs applying for a single anthopology position, for example. Even at the adjunct level, for most teaching positions, there is a tremendous oversupply.