Paid mobile game using Flare Graphics: Is it stealing?

Paid mobile game using Flare Graphics: Is it stealing?

I was scrolling through the Google Play Store, when I came across a game that looked familiar. It was called "Exiled Kindoms," and I thought it looked interesting. Upon inspecting the ingame screenshots, I recognized a few of the graphics, and the more and more I looks the more I realized that it had just taken all of the graphics from Flare and claimed them as their own. I thought it might be fine because the game was listed as free, but when I tried playing it I was required to pay $4 to play through most of the game. Is this something that they can do, and should I report the game?

Thanks!