Will advertising destroy us all? Not if the denizens of “South Park” destroy it first. That may happen in tonight’s episode, which seems poised to bring to an end several season-long storylines that are tied together through the power of advertising and marketing. They include the ramifications of the creation of an upscale neighborhood in the title town, the arrival of the town’s first Whole Foods, the replacement at South Park Elementary of long-standing Principal Victoria by the hyper-aggressive PC Principal, the infestation of the Yelpers and a covert plot by middle-age men in suits to either manage or exploit the terrifying influence of advertisements, commercials and native content that is sweeping the land. Caitlyn Jenner is a part of it all, too.