lattes are french and therefore bourgeois, real proles drink black coffee or take trucker pills.

No, not flavored coffee. PSLs. Different things. It's like saying "pork sandwiches" when someone brings up the McRib. It's not that simple. Food has a cultural component tied to its manufacture and identification. And, similar to the McRib, Starbucks style PSLs are food that probably shouldn't exist and which only does as a byproduct of market capitalism. They're the Lacanian 'object a' - an empty, manufactured falseness. We don't desire the thing itself, but the thing whose absence it symbolizes. What you're really consuming when you drink a PSL or a McRib is its innate mechanical predictability.