Seeing both sides, I would like to educate readers of this thread on the theory of Gift economics. The idea is that there is a social compulsion to return favours. You do a favour for me, thus I am socially, morally, and/or ethically, bound to return that favour. For example, should a friend invite you over for dinner, you feel compelled to return the favour by inviting them over to your place. In this way, we all feel like contributing members of society (or at least our social groups).

In this model, people who give receive prestige in return. When there is a deficit of prestige, e.g., when you cannot give as much as is given to you, you feel like a lesser person, while the giver feels like a greater person ("look at all I am able to give!"). (For the Christians out there - this is why Jesus of Nazereth told his followers to give alms in secret, since those who give alms in public have already reaped their reward - which is public prestige.)

Maybe you feel this compulsion, too, in some situations, but perhaps not in this situation. That's fine, that all depends on your choices.

Personally, I do try to contribute back what I can - as long as it is not proprietary to my job. But I cannot contribute nearly as much as I receive from CPAN. Perhaps that is part of the reason why I'm so prolific on PerlMonks.

Side note: I did not actually read the wikipedia page linked to above - my wife took sociology in university, so I'm basing my comments above on what she told me at the time, which stands a good chance of being more accurate than whatever wikipedia has, and any inaccuracies or deficiencies are purely due to my own fingers and memory - more the latter than the former, I suspect.