I don't agree with the word " not possible". to be honest, free spins do not promise 100% winnings, i know that. But for some chances, you can get a lot of money from free spins feature.
I think you got the wrong side of my word bigger amount. I am not saying that you are spinning free spins for years. I was taking bigger amount in one spin.
Means you can not win a big amount in one spin. For big amount you will spin thousands of spins than you will get this. But again you will not sure about that the withdraw is possible or not.