Being a law student, I can say that I want more class time for the classes I'm taking. (And that's mutual accross my fellow students.) What the "study" you're refering to probably really means to say is that as a practicing attorney, I won't use a lot of what I'm learning because I probably won't practice exclusively in the field. It is still a vital part of the education and even in practicing a narrow field of law, all parts will eventually impact the practice.
It would be like having a vascular surgeon not learn how the immune system works, even though the two are interconnected. Just because I'm going to be practicing international law doesn't mean that I'm not going to run into trusts & estates.
But I digress and derail....