Oh, I see! Yes not having character customization for the demo seems like a good choice.
I was cutting within the circle and completed the quest (wasn't it 2500 grass cut though, not 10,000?) and I didn't see the grass being cut down at all. I didn't change any of the settings from default but there's the faintest possibility I might have some old settings carried over from an ancient version of the game. I can try again later if you'd like, I've gotta go do some things now though.