Insert/Delete not available on Protected Sheet

[tlrowe9065]

I've got a sheet with 8 columns, 4 that the user can make entries and 4 that they cannot. I still want them to be able to insert and delete rows. I've set the protection properties to lock the columns that I want locked and got the others set to unlocked. When I protect the sheet with these options:

My locked and unlocked columns work great, but the insert and delete options are grayed out when I right click. What am I missing?

Thanks for any help!