The reason of this is not difficult to find.

In order to be a good Protestant it is necessary to "search the Scriptures," and to do this, one must be able at least to read.

To be a good member of the Greek Orthodox Church, on the contrary, according to popular conceptions, the reading of the Scriptures is not necessary, and therefore primary education has not in the eyes of the Greek Orthodox priest the same importance which it has in the eyes of the Protestant pastor.
It must be admitted that the Russian people are in a certain sense religions.

They go regularly to church on Sundays and holy-days, cross themselves repeatedly when they pass a church or Icon, take the Holy Communion at stated seasons, rigorously abstain from animal food--not only on Wednesdays and Fridays, but also during Lent and the other long fasts--make occasional pilgrimages to holy shrines, and, in a word, fulfil punctiliously the ceremonial observances which they suppose necessary for salvation.

But here their religiousness ends.