On average, an Indian domestic player takes part in a minimum of 7-8 first-class matches, in addition to a similar number of T20 and 50-over matches. So we can expect them to earn somewhere around ₹15,00,000 to ₹20,00,000 per year, on top of other perks such as daily allowances and food coupons. This might seem a low salary for those in the developed nations, but in India this is very significant.
But the thing is that while BCCI is a rich body which can afford these sort of salaries, BCB may not be able to afford it.
Even in India, the salaries used to be very low. Earlier, the Ranji Trophy players used to receive ₹10,000 per day as the match fees (until 2016-17). This was increased to ₹40,000 per day during the 2017-18 season. Also, during the same year it was decided to increase the number of first class sides from 29 to 37 by adding new teams such as Manipur and Mizoram.
I am not very happy with the domestic cricket structure in India. There are simply too many first class sides. 37 is just too many, and it drags down the quality of the game. In Australia, they have only 6 teams and the quality of the domestic cricket is perhaps the best in the world. Even in England, they have only 18 county sides. And in India, many of the states have as many as 3 first class teams (Gujarat, Maharashtra.etc).