As far as I know, cash deposit in fantasy cricket (in India) can be done only through bank accounts or using debit/credit cards. So there is no need to do KYC. None of the sites allow deposits in the form of cryptocurrency. So the government may tolerate them up to a certain limit. Also, these brands (MPL, Dream XI.etc) are heavy donators to various political parties and therefore they have good relationship with the politicians. On top of that, the government badly needs the tax revenue from such activities.
The government would not consider them illegal but, they are promoting gambling. Yes, you are right these guys might be contributing a lot to political parties that is why they are able to operate without any issue. I also believe that such apps are opening doors to another kind of gambling apps. In the near future, many more will operate without any issue.