However, if people were getting paid for fixing bugs and cleaning up old code, maybe that'd improve.
Big new headline features are a marketers wet dream.
"We fixed that annoying bug that affected 4 people last year" not so much.
Also, "driving for uber" is hardly a great thing to aspire to.
It appears they leverage Bountysource (not familiar with it).
Complaints are publicity. They bump internet discussions, create buzz, and often go along with protestations of 'I really love (FooBazBar), I promise it's the best thing ever, now if you would only fix this bug…' and then angry flames over the bugs and defenders coming to protect the honor of FooBazBar.
Fix bugs and people are happy and stop talking. They return to happily using the product. Again, we're talking perverse incentives for just the sort of obnoxious behavior you describe, or worse.
How is that good?