The "how do they make money" question has come up before. They don't answer it but they are not a publicly traded company with shareholders so they are not required to answer it. A few have even proposed some pretty wild conspiracy theories just because they they can't figure it out. Thankfully this thread hasn't dissolved into that area yet, but before spinning tales the conspiracy-minded might want to read up on Occam's Razor. Basically that says the simple answer is usually the correct one. How they make money is really not hard to figure out with just a little reading of this site's links and some thought.
The server they use, Word Press, is free. The bulletin board software they use, BB Press, is connected to Word Press and is free and open source. So subtract those expenses right there. The download server they use, filekicker, is very inexpensive.
There's two kinds of ads. Every day developers post ads for additional software that is not being offered for free. Those developer's ads are carried over to the first screen on some installations, you can shut off the screen but if you don't they're there. Next, there's Google sponsored ads on different places on the site but they are very small so you have to look for them. (Google ads aren't sinister, they are all over on safe sites. If blocked with an ad blocker all site functions still work. You can even block the script for Google ads and all site functions still work.)
So far there's not that many ads on this site but it hasn't been around very long, there probably will be more in the future. In the meantime, advertisers pay well to place ads on sites that have large numbers of users and many daily hits. Offering a new program and a new game every day that users would normally have to buy is a big draw. It guarantees most will stop by at least once every day and tell others to do the same.
This site hasn't even existed for one year. It operates out the US and even the big bad IRS says new businesses don't have to show any profit for the first three years yet can continue to deduct expenses. If still no profit after three years then further business expense deductions are disallowed and the business must redeclare itself as a hobby. Businesses can file for extensions on the three year limit if they show cause.
It's entirely possible they are not making any profit or not much of a profit at present but are banking on the future. That's not unusual, it's what entrepreneurs do. As a private (as opposed to public) business they can answer questions if they choose but are not required to supply their balance sheet to the general public. But again, it's not hard to figure out and they can deduct related expenses for at least the next three years, such as their purchase costs for software licenses and that small amount they pay to filekicker each month.
@DawnF. Thanks for reminding everyone of the limits on 'freedom of speech'. So many don't understand 'free speech' applies to the legitimate press and allows for redress of government for grievances. But this site is hardly the Fourth Estate and 'free speech' does not apply to private businesses.
As you pointed out, certain limits on 'free speech' are consistently upheld in court. You can't yell "fire!" in a crowded theatre, you can't commit libel, you can't call your boss a [insert any expletive] and expect to keep your job, you can't verbally threaten anyone, you can't make terroristic threats, you can't harass anyone, etc. etc.