Correct. Pixie Pass is always blocked on weekends, that is how the pass is sold and why it is a lot cheaper. All other AP's can be used on weekends by that time of year. Won't make any difference on locals with AP's in the parks on weekends, except for Epcot, which attracts a lot of locals from Friday evenings through the weekend, all year round, and even more so during festivals (like F&W in August). Crowds are basically at some of the lowest levels of the year at the end of August due to the heat, storms, hurricane threats, and school - locals aren't going to effect the crowd levels at the other parks all that much.