I wouldn't mind seeing single sentence google adwords in the comment sections, perhaps 1 for every 30 comments. Bonus points if they got worked into the pun threads.
Something is seriously odd, here. I used to see $25 a month or so from an art-related site that got very little traffic in comparison. Unless you were just exaggerating for effect?
First, he lives in Cupertino. Coffee there might cost $25, I'm not sure.
Then, Google payments have been declining for a long time. We tried AdSense and I STILL haven't made enough to get Google to send a check (nice how they'll hang on to your $80 to the end of time, hmm? Wonder how much free advertising Google scams that way). Then, we switched to our own ads and make approx. 800 times as much per day (not an exaggeration).
User demographics are very, very different. I'm betting most reditters are aware of Google AdSense (and consider it kind of lame?). But hardly any of your visitors may be aware of AdSense and may have actually considered as good-ol-relevant-link.
I think in a month we made enough for a cup of coffee.