Have you seen the latest Bay12 report? Professional software developers are lucky to average that much a month! I don't think we have an urgent need for an alternative revenue stream here, even if I really want to see some official Dwarf Fortress merchandise.
I just looked at the May report. Based on the income for the 5 months listed, he's making about $80K per year. But remember, that includes February, when 34.01 came out, which was probably his biggest month ever. I'm a professional software engineer, and if someone offered me that I'd laugh at them. Especially since it doesn't include anything like healthcare, which isn't cheap, or other benefits. My
base salary is more than 50% higher than that, plus I get full health care, free meals, an annual bonus, stock grants, 401K matching, and other benefits. Even looking at February, his best month due to the 34.01 release, he still falls short of what I make, considering the benefits. And his January number is equivalent to what I made my first year out of college, 20 years ago. I think my company pays interns more than that per month.
Actually, I just looked at past Bay12 reports. In the year from May 2011 to April 2012, he received $58,460.05. That's less than $5K per month, and I don't know too many professional software developer who'd feel lucky to make that much, even if it included benefits. It may sound like a lot to a student, but it's far less than half what he could be making.
I'm not saying that Toady should put ads in DF, I'm just pointing out that he's not making nearly as much money as he could if he was working professionally.
That's why I've already contributed as much for DF as I'd pay for a commercial game, and will continue contributing more in the future. I'm willing to pay more for DF than I would for other games because I understand the sacrifices he is making to create it. Plus, it's a better game.
But I wouldn't quit playing if my dwarves were drinking Captain Morgan Dwarven Rum, if that's what it took for Toady One to keep going. But I think he'd have a hard time getting it to work.