You are missing the main problem in your observation. In terms of wasting money, it's not the radiologist read, its the ordering physician. Serial repeat cxr for pna. If the patient's clinical condition is stable or improving, there is no need for daily a cxr. Particularly since the literature shows that the cxr can remain abnormal for over 4 weeks after clinical improvement. That cxr, then, is a waste of money and resources. Furthermore, as imaging has improved, its importance in evaluation has increased. In my ER, CT's are ordered by triage nurses before the patient is seen by the resident or attending. When I was a resident, it was common to get calls from the ER docs asking for results before they had even seen the patients.
One big East Coast trauma center did a study looking at physical exams on trauma patients compared with imaging findings. They found that the residents were missing too many things that should have been obvious with what the study guidelines considered an adequate physical exam. They concluded that the poor physical exams were actually a hindrance to prompt and proper treatment and removed most of it from the initial trauma evaluation.
Also, clinicians are notorious for being myopic in evaluating films. I trust the orthopod to be able to see that the anterior shoulder dislocation has been reduced. What he's gonna miss is the adeno ca sitting in the lung apex.
Lastly, adding to what Hans said, clinicians don't really want the responsibility for imaging. At one of the hospitals where I've worked, the ER docs have the ability to enter their prelim on any plain films. They enter prelims on normal cxr's, obvious wrist fractures and lobar pneumonia. But they won't touch a diabetic foot, a c-spine with disc disease, or chest film on someone older than about 55. If they want the responsibility, they have to take it all.
A few years ago, the ER wanted to be able to interpret and bill for ultrasound readings - but they did not want to say any images. That way, no one could question their findings later. This is basically self-referral, another huge expenditure black hole - best left for another thread.