Share holders don't own specific sites ^^^.
Share holders do have priority, however they can't make reservations 7 months in advance like the public. Only a percentage, 60% I believe, of sites are reserved for the public and those are the least desirable sites on the south side of the resort. Now, after you have been going there for several years you'll get to know some folks and often that will get you a better site, but you won't know till you get there. As a non-share holder you cannot expect a "luxury site" during the summer or holidays, there are just way to many share holders.
Lastly, even the worse sites at PCV are a whole lot better than a lot a other CG in the area (Across the street).