First off, I never thought young ones should have been in the main hall. It's unreasonable to expect a small, energetic child to sit quietly for two hours and not fidget, squirm, or fuss. THEY'RE CHILDREN! But, I lost count of how many bored and fidgety children were hauled off to the bathrooms and beaten. Such bullshit.
What does the org have against "Sunday school" exactly? If they're so keen on indoctrination, you would figure they would make indoctrination fun for a child by gearing things towards them. Never made any sense.
Secondly, it hurts childrens feelings when adults laughed at them. I know it hurt me. Once we had a nice visiting speaker give the public talk. In that talk he pointed out that during childhood, children want approval, love and support from adults and when they're laughed at, they learn that they're not valued. He suggested that if you want to "encourage" your children, perhaps nod your approval and smile at them instead of laugh. So what happened during the WT lesson? You got it. Some child answered with a one-word answer and everybody laughed. F...ing JWs.
But then again, I think that indoctrinating a child in any religion is abusive. Expose children to a wide variety of beliefs, including no belief at all, and encourage them to explore. When the child grows into an adult, they'll have a more rounded view. It sickens me that it is considered a good thing to indoctrinate children. I've seen some videos on Youtube of young Islamic children saying that how when they grow up, they want to be a martyr. In the JW children, they're encouraged to not become educated and to throw their lives away to pioneer. They're never taught to think critically about anything.