Having a few extra dollars a month doesn’t prevent the government from punishing you for doing something they don’t like. For example, Hong Kong is relatively wealthy compared to the rest of China, but participating a protest in Hong Kong can still lead to jail time (or far worse now). Paying them a few dollars for their data does nothing for them but potentially let them take one extra day off work per year to protest, although with the censorship and monitoring that China does, is that safe?