Surface vs. Shell print - why is there a texture on the right?

Picture here:

Somehow the "Shell" print has a weird texture/support printed inside. (I turned support off)

Why is this happening? And how can I prevent it?

The weird texture  isn't support, it's the infill to  seal the horizontal surface and incline. 

It will reduce the "Support" to select 30 Deg.  It will not disappear if there are >30 incline on the model.