Can you show me some sources for the claim that 'Chinese people do not using toilets in much of the country'? For all I know, it's the Indians and some Middle East countries that prefer water over toilet paper.
Yes I have been to China, as I was born and raised in China. I've been to small villages, towns and large cities.
I would say that very few places are actually not using toilets like the some places in north-western/south-western part of China. However, the majority of the Chinese people live in other parts along the coast and major water bodies.
I remember when I was very little, so at least 20 years ago, there were no toilets in the village I was born in. It has not remained that case since then. I would say your information is pretty stale.