How about free content that isn't ad-supported? Shouldn't sites like Wikipedia and dmoz give you more pause than an ad-blocker?
Sites like Wikepedia are donation based, and run as non-profits.
(For the record, I actually worry if my coffee purchase really does offset my resource usage when I stay for 3-4 hours in my local coffee shop on weekends.)
Theoretically speaking. See:
http://www.slate.com/id/2132576/?dupe=with_honor +
"I opened a charming neighborhood coffee shop. Then it destroyed my life."
+ No clue what that query parameter is doing there, but I got to it with Google.