Kids cry. Parents are stubborn. The excitement of the moment. The once a year or longer opportunity. The price of parking. The ubber disgust of having to return and try the line a second time. The good rides always have lines. To aggravate your parents. To aggravate your kids. To do something while drying off from the water ride. To hide. To blend. To try a different seat. To find your hat. You promised your cousin a first hand experience report. You have one barf bag left and you need to use it before you fly home.
After living up the street from Disney for 17 years, I can supply you with more answers, but you get the gist. :-)
My in-laws live in Southern California, but no Disneyland for us or the kids anymore. Several no-name parks offer similar wait times as Idlewild with prices slightly more than half the price of the Disneyland brand.
When we lived in Japan, Puroland, an amusement park run by Sanrio of Hello Kitty fame, also offered minimal wait time because tickets were sold by reservation only. They knew the park's capacity and walk-in tickets were sold only to the extent that reservations were not filled.
Brand names amusement parks simply do not care how long guests wait in line because they collect the same admission fee whether the park is at 90% or 190% capacity. The last straw for us on Disneyland was years ago when we waited in line 30 minutes to buy an overpriced ice cream cone. We resolved never to go back and have kept that promise.
LOL