Just like any other popular app, WeChat allows users to sign up for subscription accounts. This is done in order to allow people to use WeChat for different purposes. Some people may be using it for business purposes. They want to be able to advertise and promote their products for everyone to see especially their friends and families.
However, many others want to use WeChat in order to communicate with their families and not advertise, but they just want to have fun. It is simply used for their fun. However, subscription accounts can be opened in order to have more options. They want to have more functions. Sometimes, these accounts cost money, but it just depends upon what they are looking for.