I can only echo pretty much what others have been saying here already. You can certainly win off of free spins from time to time but the likelihood of actually winning something of any sizable amount or winning every often is just not that likely.
Ive won on free spins before in the past but its been quite some time and I never had won anything of much.
Yeah, that's it with free spins.
You'll win but it won't be as significant as the good amount that we usually get from betting with certain matches and high odds. It's like getting something for free and you don't expect to get the best from it.
So yes, OP you've got answers already and this thread has served its purpose.