Without a doubt "cash is king" in PRC (you see people going in and out of the banks with hundreds of thousands of RMB in bags daily) and the amount of tax paid by most is very little (if any at all). They also have anonymous shopping center "smart cards" which are often traded and can sometimes contain tens of thousands of RMB per card.
Understand that also the cost of banking (in terms of fees) is virtually zero and the cost of making internet purchases on taobao is completely fee free (with the ability to send back or get refunds) so for the vast majority there is really nothing to be gained from Bitcoin apart from perhaps escaping inflation.
I do think that Bitcoin mining is something some internet savvy Chinese would be doing as it is quite likely that they may have access to "free electricity".
The amount of tax paid by companies is very high, including the Enterprise Income Tax (as high as 25%), and the VAT (normally 17%). The personal income tax (progressive, the maximum cap is 45%) is also pre-paid before one gets her salary. There are surely many places where people could benefit from Bitcoin.
The cost of banking is also not zero, and invoked quite a lot of complaints in the last several years. If your account is opened in city A and you want to withdraw cash in city B, you might probably pay fees (in my experience, around 0.5%). The transaction fee between different banks is also non-neglectable.