I've had a few trips to DEN over Q3 and Q4 of 2015. When I arrive, I don't both with the smoking lounge, I just go outside.
Have gotten yelled at twice by employees (not sure what capacity they were, but definitely not police) that I had to walk out beyond all the shuttle / pickup / taxi lanes. I'm like .... I got about 3 lanes out to the rental car shuttle line (which is where I was headed anyway) and lit up. I never understood the problem with smoking outdoors.