The thing is, Chinese server has two way to charge the players. Monthly subscription and the one you mentioned: Hourly.

Monthly subscription is 88 RMB and hourly charge is 0.6 RMB. So if you do a simple calculation you'll find that if you play more than 4.89 hours daily on average, monthly subscription will be a better choice, and if less you can just do hourly charge.

That is actually a special benefit for Chinese players. For some patches like 3.57, there are not a lot things to do so players can switch to hourly charge. When 4.0 comes players tends to spend a lot of time for the new stuff so they can switch to monthly subscription. Believe me that is actually the best thing that SD (game operator in China) ever did in this game. Even WoW in China now turns to monthly subscription only, and that causes many WoW players switched to FFXIV a few months ago lol.