Recently I was riding through a small town's main street. Two traffic lanes in both directions, with street-side parking. Very light traffic all the time. Another cyclist just happened to be a bit in front of me. We both had no choice but to be in the traffic lane, but I was cringing as this other guy was sailing by the parked cars about as close as you could be. Well within the door zone. He was in full road kit, so not a casual cyclist and likely experienced. I just shook my head.
Fortunately nothing happened. But it's like playing Russian roulette. Do that enough, and it's going to happen. I can only assume the other rider believed he was being safe riding as far to the right as possible. But with the very light traffic and another lane cars could use, there's was no reason not to clearly take the lane.
While drivers have a responsibility to look, it's an easy mistake to make. Though I tend to look because I worry about a car taking my door off. Not riding in the door zone is just one of the many defensive riding techniques we have to use. And if traffic is too heavy and fast to take the lane, then I'd find another route or at least ride very slowly to give everyone more time to react, and to minimize the severity of a collision.