I'm inclined to agree with both FAST6191 and the OP.
Those logos stick out like a sore thumb. Couldn't they just put some regular sized text on bottom or corners?
But FAST6191 is right. Some scammers can make repros pull a fast one* over consumers by fooling them into buying something that seems legitimate, but is not.
Anyway, OP, to get on with removing these things, you wanna start with either Tile Molester or Tile Layer Pro. I recommend Tile Molester, all though it is trickier to use than Tile Layer Pro.
This is assuming that the graphics are not compressed. If they are compressed, then you need to do further research on the compression/decompression schemes, and that deserves an entire thread unto itself.
*See what I did there?