Yes, you can indeed win real money with these free spins. Some might have wager requirements that need to be met before you can withdraw the money though.
Before the free spins are turned into real money there is some work to be done first. It works like this:
* a wagering requirement is the amount of times you have to bet the bonus money. If the wagering requirement is 40x, and you have winnings from free spins worth €5, you will have to make bets worth (40x5) €200 to clear the wagering requirements.