Actually, this was at a con where zines were habitually sold and were a huge part of the culture. It was even originally known as a zine con, basically. I had done all the production myself (and the supplies were really cheap) instead of taking it to a Kinko's like a lot of people apparently did at the time, and so was able to make a lot of money on the sales.

The fannish culture of the con was supposed to be that one only sold a zine at cost, so that one didn't make a profit on the zine. I was an excessively hungry early twenty-something, though, and since at least half the people at the con were selling their zines for profit (so far as I could tell), I didn't really see what the problem was.