I'd like to point out that the 1K for Cooperstown covers the boys room, food and laundry while they are there. Cost for my rental was around $700, I split a split level house with another family. My food was minimal and cooked at the house so I'd say my total investement was around 2K.
I will agree strongly that there is nothing for the little ones to do in Cooperstown. I left my then 6 year old at home with dad and I took the boy. That worked out great for me but if you have a team with a bunch of smaller siblings I could see that as being a plus for Ripken and a minus for Cooperstown.