I can confirm this. We have a site-wide license for Matlab, but not for Mathematica. Educational version of Mathematica 7 would cost me my two monthly salaries - therefore I will pirate it.
Matlab quotes me $1900 for a single common license: http://www.mathworks.com/store/loginSubmitGuest.do while Mathematica is $1750: http://store.wolfram.com/view/app/mathematica/
How much does site license for Matlab cost you?