The only simple reason they are doing this for is that it works and is a very easy way to make money, and even tho i will not buy it there will be other 1000 stupids/dumbs that will, and that is exactly what they are looking for.
Also, since they are Chinese, they are masters of copying stuff and finding loopholes to evade being caught, the reason they took the app down is that they most likely haven't found the loophole yet.
Also Google Play Store is the best platform on which to do this considering how many ripoffs there are on it of practically everything under the sun and Google doesn't do anything about it unless it's a huge public scandal (and why would they since they get a cut out of every purchase).
I have been with PCSX2 since the days of 0.9.1 and i know how much work has been put into it, by the developers, by the users reporting bugs, by the people maintaining this forum (which i am currently just a lurker in).
You have a long battle to fight and to that i can only wish the PCSX2 team a sincere: Good Luck
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