Adverts, AdBlock and Assholes.

I use Adblock.
Let's just get that out in the open.

I also happen know widespread Adblock usage is bad for internet content providers.
But, I still use Adblock.

Before I continue, for those unaware, let me explain how the internet works and why so many people make a living on it without selling anything to you.
In every business exchange- every case where someone is being given money in exchange for something- there is a customer, a seller and a product or service. In the unusual economical systems of "free" websites that still make money, well, you usually aren't the customer.
In writing this I assume you are a Facebook user, because most people are. If you aren't, imagine you are. Or think of another free website you use for anything except buying things.
Now, there is a difference between a Facebook user and a Facebook customer. You are not a Facebook customer. You are a Facebook product. We are the collected demographics that Facebook sells to anyone who has something they want to sell to us.
You will notice on Facebook that the adverts you see are usually tied to the information you give to Facebook about yourself- the whole reason Facebook cares so much about what you "like" is so their customers- the advertising agencies and marketing departments- can find customers of their own (you). Other more specialised websites usually have a more specific demographic and are sought after by anyone wishing to advertise to that demographic.
YouTube bloggers make money off their audience through adverts.
Half the webcomics I read (well, the ones that don't have lucrative merchandising gigs going) make money on adverts.
Heck, I'm using Google AdSense on this very blog to squeeze precious pennies out of the two dozen or so views I get per post.