No, it's NOT free. TANSTAAFL. Someone is paying for it. In the case of ad-supported content, I'm paying for it. Just not with currency directly.
I happen to think the cost, personally, is too high. I'm very grateful to the people that don't block ads letting me enjoy the content without having to shell out directly from my pocketbook. I just won't be one of them. There are models that can support content that I am actually willing to lend real money to (assuming I can find a steady income stream in this dried up economy. Relying on odd jobs and charity is a crappy way to live). For instance, Patreon. I love Patreon. I hope to actually be able to support more of the artists, authors, video producers, and modders I enjoy using that service soon.
I wish there was an advertising model I trusted other than Google Adsense - which is explicitly whitelisted. I actually like the place that honest advertisement holds, it really does serve a purpose. If it wasn't for all the obnoxious and infected ads ruining it for ads in general I would greatly enjoy turning adblock off on more than 5 sites across the internet. Unfortunately we live in a world where advertisers think it's a good idea to stick megabytes of content into a page, greatly slowing its load time, ads are routinely used as attack vectors, and those ads are using horrifically dishonest tactics like flashing, animation, and those stupid plays-sound-in-the-background ads that when they occur I have to usually dig through WELL OVER A HUNDRED TABS to figure out where they're coming from, wasting my time and making me NEVER want to buy whatever product it was EVER AGAIN. I actually won't buy Mr Clean shit because of one of those ads about the "magic erasers". I wasted over an hour when you total up the time trying to find that damn infomercial, and the cleanup after as I had to re-open tabs, re-login to sites, and other tasks.
I feel the same way about ADFLY, I've installed a greasemonkey script specifically designed to let me bypass the site entirely because they couldn't police their content to keep out the fake download phishing attempts, and I still hear about the ads being used as attack vectors. Not to mention the stupid "click here to actually get the link you actually wanted in the first place" crap annoys me to no end. Sorry if you aren't getting ad revenue from me for it, but I would rather spend 15 minutes on Google to find a modpack to rip your mod from or literally any other method of obtaining your content than use that ****hole site. At least in my case, you're not losing anything.
Honestly if I talk any more about this I'm going to start a whole political rant on the subject; so I'm just going to drop it here because I feel VERY strongly about the rights of the user/consumer; which is kinda unpopular amongst the content producers in this community.