There is no reason not to compare pilot pay in the domestic American economy with other jobs bearing similar features and general qualitative definition. The subject is well- defined.

Characteristics of a profession
(Wikipedia)

There is considerable agreement about defining the characteristic features of a profession. They have a "professional association, cognitive base, institutionalized training, licensing, work autonomy, colleague control... (and) code of ethics,"[20] to which Larson then also adds, "high standards of professional and intellectual excellence," (Larson, p. 221) that "professions are occupations with special power and prestige," (Larson, p.x) and that they comprise "an exclusive elite group," (Larson, p. 20) in all societies.

Members of a profession have also been defined as "workers whose qualities of detachment, autonomy, and group allegiance are more extensive than those found among other groups...their attributes include a high degree of systematic knowledge; strong community orientation and loyalty; self-regulation; and a system of rewards defined and administered by the community of workers."[21]

A profession has been further defined as: "a special type of occupation...(possessing) corporate solidarity...prolonged specialized training in a body of abstract knowledge, and a collectivity or service orientation...a vocational sub-culture which comprises implicit codes of behaviour, generates an esprit de corps among members of the same profession, and ensures them certain occupational advantages...(also) bureaucratic structures and monopolistic privileges to perform certain types of work...professional literature, legislation, etc." [22]