What stereotypes do you believe about the various types graduate and professional students?

As a grad student currently taking a class with med students, the animosity between the two groups has become increasingly obvious to me. There seem to be stereotypes and beliefs about each type of graduate and professional student. Some people dislike (in general) certain groups more than others. I am interested in these stereotypes.

Please offer your opinions of (as well as general preferences for and dislike of) the following groups:

Graduate Students (Ph.D.s-to-be)
Medical Students (M.D.s-to-be)
Law Students (J.D.s-to-be)
Business Students (M.B.A.s-to-be)

If you want to go crazy, you can get into your stereotypes of various kinds of grad students (sciences, humanities, etc.) and even students pursuing degrees such as D.O., Psy.D., DVM, etc.