There are less airplanes that need to be flown than there are disputes to resolve (lawyer) or broken bodies to fix (doctor). Plus, there is an attraction to flying that the other professions don't have that lures people in. Compared to many professions, commercial flying is actually fairly easy to enter.

Furthermore, being a pilot is not the same as being a doctor or a lawyer or even an engineer. With the funding problem resolved, one could go from zero to commercial pilot, CFI, II, MEI and several hundred hours logged within a single year. Med school and law school, by comparison, take significantly longer and a much greater investment.

Furthermore, the very students who are trying to build flying experience turn into the teachers in many cases. Compare that precedent to that of university professors which are mostly required to hold doctorate degrees and have worked in industry for years. You can find a CFI for a dime a dozen now days with a simple Google search. Its tougher to find a path into a profession that governs its own entrants/standards whether it be through the Bar, AICPA, or AMA.

Just because one pursues his/her dream to fly, which satisfies a deep personal purpose in many cases and is generally a fun pursuit, as opposed to sitting in a college classroom listening to a law lecture, and comes out with a license doesn't mean one is entitled to anything.

Professional aviation is great to those who make it. They may call it luck, perseverance, or sheer skill - or whatever label is attached to it. However, the supply exceeds demand right now, and the regionals were touted as a stepping stone, luring in those who were trying to time build, and turned out not to be. Now we've got a group of pilots in the regionals who are upset at the status quo and the streets are filled with furloughees longing for a recall despite their complaints.