Plagiarism laws aren't just about whether you copied from someone else. A lot of times, certainly in all the universities I've been part of, they will penalize you if you did not take reasonable precautions to ensure that others did not copy from you. There's nothing unreasonable about this.
As far as the rest of your comment goes, maybe there are some cases when students are unfairly penalized for hard-to-follow policies. But the instance here seems pretty clear cut. I also think shady behavior from students more often than not goes unpunished, so your fears of a power-drunk university arbitrary destroying students' GPA just for the heck of it, seem unjustified.
As far as the rest of your comment goes, maybe there are some cases when students are unfairly penalized for hard-to-follow policies. But the instance here seems pretty clear cut. I also think shady behavior from students more often than not goes unpunished, so your fears of a power-drunk university arbitrary destroying students' GPA just for the heck of it, seem unjustified.