Sadly the answer is, as usual, middle class ignorant teen girls and women.
I don't want to start a whole high culture/low culture debate but all these companies that promote only gluttony, whether they sell clothes, food, or 'an experience', aim at women who have some money but no real sense of art or culture, and who think they can acquire status, style and glamour by buying expensive brands and food in large volumes. Corissa and Tess are prime examples but that thinner girl in the video stuffing her face is just as bad. Those companies have mastered making their target audience feel like they are participating in something classy, while the actual rich and elite wouldn't be caught dead buying there (and they don't let themselves become deathfats).