Why are drivers in Denver afraid of honking?

I've been in Denver since 2013 (having come from Los Angeles and then Minnesota before that) and one thing I've always noticed is that drivers seem to be incredibly hesitant to honk.

Here's a scenario from today: I'm waiting to make a left turn, about 5-6 cars back from the front. Light turns green. I wait 3 seconds and no one moves. So I give a small honk because...no one else does. Cars still don't move, and it's a pretty short turn light.

I finally lay on my horn and 3 seconds into that, the front car finally realizes they need to go, and starts going, but of course now the light turns yellow before he even completes his turn, and myself and two other cars in front of me have to wait through a whole other cycle.

What I can't comprehend is how no one in between myself and the front car bothered to honk! This is not the first time this has happened to me. It's like the drivers would rather just wait and hope the person driving in the front car notices than be considered impolite. I have not experienced this in any other city I've driven in.