Millions of poor Indians are considered criminal by tradition. Most are nothing of the sort

If they were crooks, wouldn't they be richer?

"This stigma goes back over a century. Mostly itinerant—some blue-eyed Pardhis look like they might come from the far north-west—India’s “criminal tribes” have always lived on society’s edge. Yet their plight was made worse by a series of 19th-century changes, including rapid deforestation, which stopped them from hunting, and the imposition of a tax on salt, which many had traded. No doubt this drove many to crime—which encouraged India’s British rulers to a harsh conclusion. Imbued with a bureaucratic aversion to nomadism and a Victorian relish for the Hindu caste system, they adjudged many Indian tribesmen, Pardhis included, to be preordained crooks. According to an 1880 report of the Bombay Presidency, an area dominated by the modern states of Maharashtra and Gujarat, members of a Pardhi sub-tribe are “always ragged and dirty, walking with a sneaking gait”.
The Economist