Here's the answer from an anonymous source who makes a great deal of sense:
"They will buy the scanners anyway, so we might as well read for them, and thereby not anger them and lose other business."
"The patients deserve the best reads that only we can provide."
"If we don't read for them someone else will..."
The answer is that you can never justify doing something wrong because somebody else will if you don't. That condition is always true and always will be true, and could be used to rationalize any nefarious act. This type of logic didn't hold water at Nurenberg and still doesn't.
You can't live your life according to what other people might do. You can only control what you do and face the consequences. The consequences of refraining from unethical medical practice is that you gain self-respect. You may, in the very short term, sacrifice 10% of an income that already places you among the top of U.S. incomes and among to top medical specialists. You might slip a little in the short run. In the long run, you will do better financially by not participating.
The consequences of participating is that you lose self-respect, and must live with the constant understanding that at some point you are going to have to explain all of this to your family, friends, and community. And despite the positive very short term finanicical consequence of participating, you should realize that the long term negative consequences have already hit you and will only get worse--in that you have already suffered a 10-30% in CT, MRI, and PET reimbursement because of radiologists widespread participation in self-referral.
Think about it.