The government may expand the indirect tax net over cryptocurrencies to cover the entire gamut of activities, including their usage for exchanging goods and services, at the highest slab of 28% as many parliamentarians have demanded to treat them at par with lotteries and gambling, two people aware of the development said.Although the finance ministry has already imposed a 30% income tax on earnings from virtual digital asset transactions from April 1, there are still several aspects pertaining to goods and service tax on cryptocurrencies, such as its mining, sale and purchase, and their exchange value when used for buying or bartering goods and services. This matter is under consideration as all such activities may attract GST, they said, requesting anonymity.