Here's the thing - trees are not something that is going to ruin my, or really anybody else's enjoyment, of the game. What matters to me is whether or not the game is fun, and in the case of a racing game, whether the game can maintain a solid frame rate while providing some eye candy to enjoy. (Which FM7 does, in spades)
Trees are the lowest priority thing I can think of when it comes to graphical fidelity. The ability to provide 60 FPS gameplay with weather effects added in is important. ****ing trees are not.