There are no answers to the difference in tuition prices that don't lead to uncomfortable social comparisons of two countries. It depends on if you believe education markets are efficient or not, meaning the true value will be reflected in the price. Two things that would make a degree worth less are limited access to education and limited social mobility for degree holders. Free also does not mean unlimited access.
What do you mean by unlimited access? Sure, there is only a limited amount of university places, but it does not matter what is your social situation or how much money you currently have - you can study law or medicine just the same as a rich guy, as long as you have good grades that allow you to get into the university in the first place. But if you did study hard and got good grades, any degree you could choose is 100% free.
By unlimited access I mean discrimination. Two key tools used to hide discrimination are extra-curriculars and subjective entrance interviews, both of which can be present in totally free schools.
In Ireland for well over 90% of degree courses it's blind marked exams all the way. In Britain apart from Oxbridge it is again exam marks all the way (big apart from). In France I think ENA is the only school with entrance exams/interviews but much like Oxbridge acceptance means you are part of the ruling/upper class unless you choose to throw it away. German universities don't do entrance interviews, they do exam ranking and brutal weedout classes.
The USA is more or less unique in the blatancy of the class values implicit in its university entrance requirements. The cancer spreads, much like professional graduate degrees but it is still most obvious in the land of origin. Gotta keep them Jews out, or nowadays them Asians. It's about the right sort of extracurricular, don't you know?
They are not present in my country. All that matters is just your grades from the Matura exams(think English GCSE exams). It does not matter if you were a golden medalist seven times or ran your own company by the age of 14. On top of that, the Head of the university normally can assign an additional 4 places per year as he/she wishes, so they usually go to people who are talented,but happened to get bad grades in their exams, for any reasons. This is the only moment when your personal circumstances can have any effect on your place at university. Other than that, it does not matter whatever you are rich,poor, white or black - if you got good grades, you will get a place.
It would seem that the market is not efficient, since the average cost of tertiary education has risen a lot in the last decade(s) (from what I've read).
