When you're doing the same kata at the same time, you're supposed to all end at the same time. When you have black belts doing poor technique, avoiding techniques altogether, losing balance, and going through the motions it shows a lack of discipline and standards because black belts are supposed to understand this, and have enough self respect to not look like an embarrassment to their school and their art.
Underprivileged does not mean disabled. Underpriviledged usually means economically disadvantaged, and there's plenty of Karate schools in poor areas of the country that would run circles around these guys.