You can be “richly compensated for” your time and efforts in ways that are far, far more important than money. In this business, your work speaks volumes for you. It might well be the only thing that does. Your work is more important than who you have worked for, or what corner-offices you have sat in from time to time. If you can say, “I wrote Template::Toolkit,” or DBI or what-have-you, or even that I was a significant contributor to it, then this speaks far more about you than any resume could possibly do.
Then, there is also the reality that code contributions are, by far, the best way to move computer programming forward, to the benefit of the entire community as a group. “A rising tide lifts all boats.” Instead of hoping that enough people will buy your product to enable it to reach critical mass, you assure that the Perl system will reach and maintain critical mass, to the resulting benefit of everyone. You can then make your money in plenty of other ways.