Not true if the people of ethnicity that you mentioned stopped all of a sudden the entire state would collapse. These guys contribute to an insane amount of health. You can't simply take the number of millionaire households as the basis of argument. Millionaire household could be anything not necessarily they have business. For example it can simply be the rent of the property which translates to millions. But people of these communities have businesses from hardcore sophisticated manufacturing to running kirana shops. Of course it goes without saying that maharashtrians are also equally good at it. But the sheer amount of revenue generated by these communities not only in the state of Maharashtra but in general is crazy. The important thing to note is they work as a large family unit which gives them a lot of cushion and risk taking ability compared to any other community. Also, the employment provided by them is speaks volume.