That is a good point, and I agree with you when the case is that the idea or person you disagree with is a necessary part of the curriculum/class. But in the case where it's an extracurricular activity or student organization that isn't a core part of the degree, then why doesn't a student have the right to complain?

edit: I believe that students are also consumers. The two are not mutually exclusive. Tuition is pretty high these days. I guess the difficult part is finding the right balance.

Most of the times these clubs that pay for speakers are given a stipend to spend on events from the school. When universities bring in people like Ben Shapiro or Milo Yiannopoulos, it is almost always the campus Republican group that pays, in part with the money provided by the school, and in part with money raised by the group itself. Campus Democrats also get money for the exact same purpose.

I would say that the students certainly do have the right to complain and protest as long as it is not violent and not terribly disruptive. Complaining and protesting is PART of the open exchange of ideas. Physically blockading events is not, shouting down speakers while they are speaking is not, and in general throwing an adult-sized tantrum until you get your way is not.

Why should student A who sees the negative of a speaker have the power of veto over student B who sees the positive of the speaker? What happens when student B complains about a speaker that student A wants to hear? Do we just ban everybody or allow a diversity of opinions?

For that matter, if the speaker is invited by a student organization that the complaining student is not a member of, why should that student complain? Just don't go.

Why not allow both? The group can have their speaker within whatever guidelines the school has (some schools ban foul language or other school-wide policies), and the other group is allowed to protest. Just like the real world where another company can do what it wants within the law, but I can also protest what and how they do it.

Protesting the speaker's ideas is always fine.

Protesting the speaker's existence is difficult to intellectually justify as a healthy exchange of ideas, including critique.

These days, what we see is a lot of the latter -- up to and including attempting to prevent attendance of the event -- and very little of the former.

I've seen cases on college campuses of obvious criminal activity, although usually minor, that is excused because they happen during a protest.