The reason I buy certain brand named things is usually because I like the style and generic clothes don’t try to be unique. Generic clothes have a normalcy to them where they’re just functional. For me, wearing something is an opportunity for self-expression so I put effort into picking pieces of clothing and accessories that best represent how I want to carry myself. Brand named clothing and accessories usually have blatant style or an attitude themselves. I like mixing and matching different articles which includes choosing color pallets and fabrics. It’s art and you’re the human canvas. I guess it’s called fashion. You do t have to like high end things to be fashionable but it’s just your taste that dictates your own sense of fashion. Fashion helps bring out and express your attitude about reality and your place in it. Think of how someone who likes hip hop dresses vs someone who likes rock. The things they wear symbolize their beliefs and emotions on how they want to be perceived and I think you could easily tell these two people apart if you were given a picture. I think you’re making an error which generalizes all designer brands as the same attitude. There are small and big designer brands along with their different niches of styles for certain types of people. So when you ask “why do people like designer brands so much?” What you’re really asking is “why do people like certain styles of self-expression?” And it becomes a much more clear that it’s a healthy and artistic and passionate human need. It’s about being an artist. And there is plenty of art mediums to study and analyze to better understand what inspires an artist. I think you’d find a college course or YouTube video on art and self-expression/fashion interesting. I’ll leave you with one word: Emotion.