Sorry if this isn't a correct place to ask this question. I don't understand how non-profit organization exist in capitalism because how do they sustain themselves? How do they pay their workers if they aren't generating any profit? Isn't it just volunteering?
Profit is the money left over after paying your employees and other expenses.
Non-profit does not necessarily mean they won’t earn a profit, it just means their goal is to not earn a profit.
So if they project that they will receive enough donations to earn a profit, they may choose to use more money to further their charitable activities, give their exec bonuses, advertising, etc.
Sometimes, they will fall short in spending and retain a profit.