With the accession of East European countries to the EU, many of them had to unify education prices -there wouldn't be a differentiation : different price lists for foreigners and indigenous peolpe. But let's look at this - is education the first branch that had to impose unification ? Probably yes if we recognize education as a whole and with no difference when it's held in different countries.
Education prices, on the other hand, are based on other factors, not only staff's salary - such as expenses on real estates and even the far connection of whether children can live by rent near school they've chosen by interest, not by location preference.
Let's look at real property prices in East Europe and the opportunity to form a fair competition when edu prices are equal for all. Foreigners buy housings here, they increase the price or rather construction companies take advantage of the solvency.
Foreigners may be not constant rezidents,and we could rent their properties but not at the common price which is very high. And there must be a stimulating tax deduction..