Demonetization will not reduce corruption in India, because the innovative corrupt powerful indian government employees have always found ways to take bribes in ways that are not easily detectible.
While cash payment can be traced and the person charged for corruption, one of the favored ways of bribing officials is by supplying all food and grocery rations for free according to number of online sources. The local grocery shop will supply all the rations to the house of the government employee and may be compensated by the bribe giver for the cost of rations.
Similarly other suppliers and service providers are providing free products and services to the indian government employees, so they have to withdraw very less money from their monthly salary towards their regular expenses . As a result, government employees are most reliable customers for service providers, lenders, real estate companies, and now these companies are offering special discounts to government employees