I haven't missed a DT tour since '97, and when I'm there, especially when we're lucky enough to get seats close to the stage, I'm anything but dormant. I do sing along sometimes myself, but to myself. I don't try to kid myself into hearing that the band can actually hear my voice over what they have in their monitors (especially now that they're always right in their ears).
And I don't hate the crowds, especially at DT shows, because it's like you have this deep connection with everyone you talk to. I love the crowds, I can just do without people singing the songs at the tops of their lungs. It's their right to do so and I understand that, I just don't like it.