Google Play's single biggest problem
But its relatively open nature comes with another problem, and one may argue that this is its single biggest problem:
Apps that provide zero value to the user without them noticing.
"Virus Shield" is only the latest example [2]. There are myriads of other apps that similarly do "nothing". Most of them are removed, eventually, but at that point, they have already deceived tons of users. As they come up time and again, they collectively do harm to tens (or hundreds) of millions of users.
If you need more examples, search for "Telegram" [3] and see how a single app has deceived 100,000+ users already [4]. Search for "ask.fm" [5] to see the same with 500,000+ users [6].
You can report those apps, but Google is not likely to do anything about it. They're probably employing a system where manual inquiries are only done for the apps reported most frequently. And as users don't notice, they can't report.
One may argue that the the affected companies (Telegram, ask.fm, etc.) must talk to Google here. But it's not just their problem ...
[1] https://news.ycombinator.com/item?id=7544864 [2] http://www.androidpolice.com/2014/04/06/the-1-new-paid-app-in-the-play-store-costs-4-has-over-10000-downloads-a-4-7-star-rating-and-its-a-total-scam/ [3] https://play.google.com/store/search?q=telegram&c=apps [4] https://play.google.com/store/apps/details?id=angryinvadersappstudios.telegramnotesv2 [5] https://play.google.com/store/search?q=ask.fm&c=apps [6] https://play.google.com/store/apps/details?id=com.wAskApp