Lol, seriously?
Is the building the restaurant is in part of the campus or not? (my guess is, no) That's pretty much the beginning and the end of it. 269-10J doesn't have "cooties" and infect things it touches.
BTW the few cases I've seen where someone got busted for MGL-269-10J someone was
actually traipsing around on campus (for example, there was that guy that got busted with the 2 handguns after he turned around at the security checkpoint at the graduation last year or whenever it was).
The biggest "sneaky" risk to most people with 269-10J is if you're operating as a pedestrian, don't take shortcuts through college campuses. The risk there is pretty obvious.
-Mike