Don't think anyone would "turn someone in" in particular to answer you but it happens all the time. Commercial software businesses thrive on open source, and even of the successful ones only _very_ few concern themselves with giving back to the individuals whose work they used or the open-source world in any way.
(edit) I'm not against it per se, but it's sad how it's only take, take, and take.
Yeah I feel you, but think about it from the other perspective. We use PostgreSQL but may not have the expertise or budget (since man hours = cost) to contribute to the project. Open Source is and can only thrive by the amazing volunteers that contribute to them, it can never been an obligation; specially for appearances sake.