We lived in Whittier but we would pack the RV and go in that. We could arrive early and get good parking, have a place to go for a nap (my dad and the little ones), and my dad packed a few 'cold ones'. Mom would make a big spaghetti pot the day before and we would rest and have a big dinner in the RV. Then back to the park for the late night if the park was staying open late.
Never underestimate the power of stupid people in large groups.