I was speaking more to the 10/11 year old, but I don't think 6 is too young to get a little lemonade stand going. It reminds me of a kid (about 8 years old) that was selling lemonade on a really dead street shouting "get your lemonade." The first thing that came to mind is that this kid will appreciate how hard it is to make a sale before he's a teenager.

My guess is that most kids would rather play than sell lemonade, so he was probably pushed by his parents to do this.