Over the past couple of decades in the U.S. the trend in many states has been to cut public funding of the university systems. Universities have thus been forced to look around for other revenue streams/ways to save money. This has been a key contributing factor to the student loan crisis, as raising tuition and fees to get access to a limitless stream of federal loan dollars via their students is a way to make up some of the loss from cuts in public funding. Selling previously in-house managed services (campus bookstores, dining, etc.) to private contractors is another. Often you will see campus bookstores managed by Barnes and Noble, dining facilities managed by Chartwells and the like because they pay the university for this and then pass the cost on to the students. Another issue here is the currently popular trend of trying to lure in more students by constructing opulent facilities for them... gyms with giant pools, student unions with fancy dining, rock climbing walls, etc. etc.

Adding additional "fees" on to students semester bills is yet another method of raising needed (or wanted) revenue. These fees often aren't even covered for students on scholarship, and can add up at a university with 20-30 thousand students each paying 300/semester. So basically yeah, this is a "dining fee" but the money is being used for things like the construction of a new student union where, ostensibly, dining will take place. Likely this was seen by some administrator as more palatable than simply raising the probably already high student fees that already exist (athletic fees and activities fees are common ones). It all goes back to schools needing to make up revenue that once came from public coffers...