I’m seeing the exact same thing (50–100 downloads per day). At first assumed someone was promoting my app as a way to learn English (it’s a word game), but I’m seeing 0 sessions from China.
Now I suspect these are bots are just downloading lots of free apps in order to make the accounts look legit to Apple. Then they can be used to artificially inflate downloads of desired apps, without looking as suspicious. i.e, lets say you have 100,000 fake accounts. Have each one download 1000 random apps over a few months. Then have all of them download the app you want to promote.