I can assure you “some” of the database and forum mods have not developed this weird notion that official content should be paid for. We all have that notion.
It has been C3’s policy from the beginning that this would not be a place for sharing official content, only customs. I’m sure I don’t have to convince anyone that paying for content is the right thing to do, but even beyond that, it’s a matter of simple survival. Harmonix is well aware of the customs community, and is also well aware that C3 makes an extra effort not to indulge in sharing their content, encouraging people to buy it instead. That’s why C3 has been allowed to survive without provoking the ire of Harmonix or their lawyers.
As for RBN and other songs no longer available, I share in the frustration of these songs being off the table for players who didn’t get the chance to buy them. However, we still cannot allow sharing of those songs, because there is always the chance Harmonix will relicense those songs and make them available again. Harmonix has done this several times already, in fact, and continues to do so, both with RBN songs and with older on-disc songs that can no longer be exported. Therefore we have to avoid even the possibility that we could be robbing Harmonix of sales, now or in the future.