I don't understand way kale can't be used because it does look good. My guess would be that it is because it is part of the cabbage family rather than the lettuce family.
I had to alert my table captain that a box had kale in it at a recent contest. She hadn't noticed. We had to give the box a 1 in appearance.
Assassin Smoker; Large BGE; Char-Broil Gasser; Black Thermapen; Looftlighter; KCBS CBJ