Profits are already profits! This cash-out feature in some gambling platforms is new because, in old or traditional gambling platforms, you can't do this.
And many still don't like it. They're given a chance to withdraw their profits while they can if ever they want to pull off their bets.
But if they don't want to take their profits and still want to proceed, it's okay and if they want to continue with the traditional approach.
I believe that many of us are use to the traditional way of gambling which is either you win 100% of your bet or you lose it. But after the introduction of online gambling, cash out offer was among one of its features. Therefore, you have to option to be contented with the outcome of some of your games and cash out, or have the gut and confidence to see the end of all the games on your slip. I prefer to cash out and forget about the outcome of my last game.
There are still gamblers that does that. They won't stop until they've won 100% of their bankroll for which is hard to reach to be honest.
Sometimes it happens but it usually don't and that's why it is best for everyone to check it out before doing so because not everyone will be hitting 100% of bankroll if that's the condition before withdrawing.