ethics - Can authors from certain origins really not know about the gravity of plagiarism?

With respect to some cultures, in particular Asian ones, one often hears statements such as the following:

In this country, copying is regarded as flattery and thus people do not know the evils of plagiarism.

or (taken from here):

In some traditional cultures in Asia and the Middle East, for example, college students are expected to quote or paraphrase the best known political or religious authorities without attribution because readers, especially professors, are expected to know what texts are being circulated. Indeed, it might be a serious insult to the teacher if the student writer formally cites the text being borrowed.

Such statements may nourish prejudices or lead to it being considered an extenuating circumstance that a plagiarist comes from a such a country (see, e.g., this answer or this case). I wonder whether this phenomenon really has the extents that would justify the latter, more specifically: Is it conceivable that somebody makes it to the point where they author a paper or a PhD thesis without knowing that they must not plagiarise? Or: Can authors really commit plagiarism out of inexperience on this level?

Note:

• I am primarily interested in anything going beyond personal experience (there are individual statements in this article). A scientific study would be ideal, but is probably not the only possible way to fulfill this criterion.


• This is not directly about how the respective academic cultures nourish plagiarism and what aspect of the culture is behind this.

As all the answers so far have ignored this: I am not asking whether cultures differ in their attitude towards plagiarism – they clearly do. I am asking whether these differences reach a certain level.