In the elite law school universe--with huge endowments and ample resources, with large faculties, with graduates who become corporate lawyers and donate more money, with graduates who become academically-oriented law school professors--the interdisciplinary movement can be justified.
In the non-elite law school universe--with schools almost entirely dependent upon tuition, with a majority of graduates who do not get corporate law jobs and only rarely become law professors--the interdisciplinary movement cannot be so easily justified.
Let me just give three reasons why it might be a bad idea for non-elite law schools. First and foremost, as argued above, there is no evidence that it will make their students better lawyers. Second, it costs a lot of money to go interdisciplinary, and (because non-elite schools are tuition driven) this money will come out of the pockets of the students. Third, their education might suffer if their faculties emulate the elite law school trend toward hiring JD/PhDs with little or no practice experience (assuming a person with some experience in the practice of law has a bit more insight to impart to students about how to be good lawyers).