This has also been a problem with the SAT for a long time in China. This one appears to be the most recent instance of the problem:

http://www.washingtonpost.com/blogs/answer-sheet/wp/2015/03/...

This same thing also continues and becomes ingrained in academia:

http://www.economist.com/news/china/21586845-flawed-system-j...

I'm not sure if it's a cultural thing as you say or what, but I have heard of universities just assuming all numbers from Chinese national applicants have been doctored.