What exactly did they actually (in an objective sense) do wrong though?

If the only thing they did wrong was "failing to comply with regulations", then maybe those regulations are wrong. The same way that googling certain terms isn't wrong, putting labels on bottles of liquid isn't wrong. And, if someone comes to your door with guns in their hand because of this, then they're in the wrong - not you.

> You don't want to mess with the ATF. They are notorious for bringing down the hammer.

Wow, the tone people use to describe these various gov't agencies just keep making them sound more and more like common gangsters...