Since exchanges are not allowed to work in India, I don't agree with you on this one. Even if government issues some regulations regarding Bitcoin, it doesn't mean government can actually track all transactions done by traders. It can only give guidelines and it's up to traders whether they follow those or not. There will be very minute chances that government could actually catch the frauds in crytpo transactions.
If there is a regulation in India and if exchanges have to function in a proper manner they need to comply with all the KYC/AML regulation and even without any regulation all the exchanges were complying with those policies and if you are using fiat currency to purchase the coins then you need to use bank account and all the transactions are accounted for, so the only transaction that cannot have a record is face to face transaction and it has its own risk.
It is very easy to do bank-to-bank transactions without using exchange sites. There are escrows out there who can help you to carry out anonymous trading without any need to meet face-to-face. There is no track that the amount you received in bank or the amount you paid out is linked to Bitcoin buy/sell transaction. Even there are few P2P Exchanges which don't have KYC requirement. So no-one can relate transactions with any specific user there too.