I have a question about staking with the mint() function. When I generate the transaction using the contract 0xee609fe292128cad03b786dbb9bc2634ccdbe7fc I get few POS tokens but I also have to pay Tx fee. I used to think mint() function doesn't charge you fees but today I saw that I had to pay 0.00213838 Ether ($0.63).

So my question is: Is there a way to stake POSToken without paying those transaction fees that you get charged by mint function. I am used to classic wallet staking (for example DeepOnion coin, Gopnik coin...) where you just leave your wallet running and you receive interests for staking and you don't need to pay any transaction fees. I think this way of staking is better than mint staking.
Maybe I just need to wait more time and generate that mint function only once per month so I will not pay fees so often.