If I wanted a lot of carbs with some protein, I could always eat quinoa or something. There's no shortage of options there. What's interesting here is a vegan protein source that's actually a nearly pure protein source.

When you are targeting specific macros for athletic reasons, a pure protein source is pretty much a requirement. During aggressive cuts, you require a tremendous amount of protein to prevent muscle wasting. For endurance athletes, low carb diets can be useful for increasing lactate threshold. There are also low carb requirements for diabetes and epilepsy.