Well, 30k-100k is about right for the annual cost of undergrad in the US and school costs are much more commonly discussed as per year than in total around here.
>My point is that the statement that salaries can be low because university has no cost is wrong. The cost is significant even without tuition and therefore salaries absolutely matter.
That seems a bit misleading as well. Almost all of that cost is unrelated to university attendance. People incur costs for food and rent regardless of whether they're university students.