Doesn't matter to me if protesters are university students or not.
Now, if they're paid agitators, that's different
To me, it does sort of matter whether they're university students. They're protesting at a university, and in many cases, asking for concessions/actions from the university to cease doing business / having relationships with certain organizations/etc seen as supporting the Israeli actions. As students, they have a right IMHO to express their displeasure against their future alma mater when they think it's doing wrong.
It's like if you were a Congressman and I bussed in a bunch of voters from other districts to protest some vote you were planning to make. If you simply counted numbers, you might think that a bunch of your constituents were against your vote. But if 50% of those protesters were from a state or two away, you might misread your own constituents' opinion on the matter.
Now, I'm not saying it should be
illegal for non-students to protest a university or for non-constituents to protest a Congressman, but I think knowledge that it's occurring waters down the impact of the protest in a very significant way.