Of course it is necessary, when we transact a cryptocurrency miners are the one who verify or confirm the transaction you have made and for miners to do that effectively, they need a lot of resources such as electricity and efficient hardware, you have to understand that cryptocurrencies are decentralized so there is no central entity that is responsible for processing all the transactions, and no one will do it for charity, of course people will mine what is a coin that will give them the most profit. It is like transferring money using banks but in a cheaper and fastest way so there is no need to protest for this.