Imaging is certainly over-utilized. When I was a senior resident and fellow, I would routinely deny unnecessary and ridiculous imaging requests. I would give an excellent tutorial explaining why the requested study was redundant or would not answer the clinical question, and most commonly they would resist. I am not sure whether they were just clueless, stubborn or egotistical. It was so laughable that a PGY2 or 3 internal medicine resident would try to lecture me (as a fellow) on cross-sectional imaging. It seems PACS makes everyone think they can do our job, until EPIC goes down for 1 hr and they begin to call the reading room frantically for verbal reads.
At times the residents, fellows and attendings would escalate denials to the section chiefs or, on rare occasions, the chair of radiology. In the unusual situation that the section chief agreed to perform the study, I would routinely call the result in so they knew that they just wasted everyone's time and money (in a nice way). It is one thing if the doc is overworked and does not have time to think, but if I have taken the time to explain why a study should not be performed and you still insist, then I begin to question your intelligence or intellectual humility.