Seems to be standard practice for Chinese companies. I like the look of some of Onyx's ebook products, but I've refrained from being tempted as they have been in violation for ages. Unless you are a huge company there is very little you can do. There is probably very little you can do even if you are a huge company. Enforcing our laws & licences over there is nigh on impossible, and appealing to their laws is pointless as the government seems to very openly not care about such violations (some would say their attitude practically encourages such violations) unless they happen against one of their interests. This is not at all specific to open-source licences either.

My current phone is a Xiaomi, looks like my next one won't be (it may not have been anyway, due to a list of minor irritations & larger red flags like impossible to uninstall apps and a default clock app that demands full contacts access in order to be able to set an alarm, but this is definitely another point against).