It is really up to the person who is playing if he or she use his or her profit. But I do not urge on using the profit because that's my win. If I lose those I will go home without any money. But what I'm doing is if I already won I will go home. So winning something that exceeds my first money is equal to my house haha.
I always prefer to play with the winning amount. Here I have certain regulations that if won I used to save half the amount in a separate wallet that's used for saving from gambling. With the remaining half I used to play. It gives the stubborn mind to predict more precise as the failure won't affect me, as I have a small winning already.
It is hard to believe that you are making profit in gambling in long run. You have to lose at some point, you can't win all the time, and when you lose that half do you gamble with saved money or do you deposit "new" money? Especially if you are playing games with negative expected value then such strategy can't be working one.