I agree with taking them out. They don't fit that well to the point that I can't imagine anyone seriously using them. More to the point, you can't even use them easily- you would have to put part of the grass-topped ground into layer 5 (needless to say it's never a good thing to force people to use layer 5 as a support layer for 4) so that they would be standing on the ground, not floating over it or in front of it.