Debian does have general policies and a culture. (Yes, we could say it's just a bunch of files on a bunch of FTP servers, but we can agree that that's stupid, right?)
As to the bug report thing, let me clarify: why should upstream authors have to pay the support cost (in e.g. time and negative impressions of them) for bugs introduced by Debian's packagers?
> why should upstream authors have to pay the support cost (in e.g. time and negative impressions of them) for bugs introduced by Debian's packagers?
They are just as capable of saying "that's a Debian bug, go file a bug report there". That's a small price to pay for being open source, in any case. Debian certainly picks up bugs that are intended for upstream, and there are certainly instances when Debian maintainers have been quite helpful with fixing them. And others where they haven't been. With that many people there are bound to be some really good ones, and some that are below average...
"That's a Debian bug" is not useful - you can only determine that after you have analyzed the bug thoroughly, and gone to the length of getting out a Debian system instead of whatever you're usually developing on.
But yes, some maintainers are very good and some are quite bad; however, Debian's policies and patch-happiness means that bad maintainers (can/tend to) do much more damage than in other distributions/OSes.
Well if you really want to play tough about it you just say that all bug reports for your software running on Debian must go through the package maintainer. You could even ignore them if you get a lot of bogus ones.
Yes, but even that is a half-solution - Debian users are still likely to think you suck and/or use alternatives, which means less users/prospective developers/testing.
As to the bug report thing, let me clarify: why should upstream authors have to pay the support cost (in e.g. time and negative impressions of them) for bugs introduced by Debian's packagers?