I got tired of the thankless task of doing other peoples' work, along with the overzealous mods shutting down my questions in the most condescending tone possible. In particular, I recall going so far as to read vendor-specific documentation for someone, and providing example code to parse the binary data in question. It was probably an hour of my work and I didn't even get a 'thank you', much less any reputation bum…
I actually don’t use Stack Overflow as a contributor for precisely the same reason: I created my account with an OpenID, the provider is no longer around, and now I can’t log in nor fix it.
I guess it supports other options now, but back in the day, that's why I never participated.