I'm sure you appreciate others advertising your site for you at no cost to you; that's a benefit with a tangible, monetary value. But, that's fine. People can spend their money any way they want. No need to be so touchy about it, IMO.
Further clarification, though with your response I'm not sure you deserve more, when I wrote "make money" the phrase doesn't mean "getting rich" or "clearing a profit" or "positive return on investment" of this site. What it means in financial terms is "generating revenue." I have no doubt that this site is run financially as a service rather than a profit center. However, those flags can generate value, i.e. money.
For example, let's 1000 people see a flag. Of those 1000, 25 people join the site, of those 25 people, 2 pay dues. Viola, money maker, revenue generator, tangible monetary value.