Just deal with it. Run as little as possible, that's what I do, or just make paths, or put down patterns so where you run, the grass doesn't wear away.
If you email them asking ANY question about an upcoming game, all they do is blow you off by saying they "can't answer your question at the current state of the game" I did it twice!
Ok guys, there is really no need to post here anymore, My question was already answered by a helpfull person, and I guess nintendo is not going to e-mail me back.