All Indian tribes are now rich. Tribal gaming is an unregulated magnet for organized crime. Large-scale tribal gaming predated IGRA by about 10 years. The Supreme Court found that California's gambling laws are civil regulatory, and thus could not be enforced against tribal gaming on a reservation. IGRA, in fact, limits and constrains the tribal rights recognized in Cabazon.
Indian tribes are governments.
Gaming on Indian reservations is operated by tribes to fund governmental programs. Tribal governments, like local and state governments, have responsibility for the lives and well-being of their citizens. Like non-Tribal governments, Tribes must face the housing, medical, hunger, education and job training needs of their members. Tribes are thus neither charities nor commercial enterprises. They are governments and have been recognized as such for hundreds of years, most recently by the last six Presidents.