When I was growing up as a kid in the 80's my parents owned a brownstone. Three floors and a basement. From top to bottom it was all close relatives, including all my mothers unmarried brothers and sisters, her married sister and her family, my brother, my sister and my mom's mom.
So... Going to Pathmark each week was a whole operation that ended with two whole shopping carts of stuff coming home. With her own children and others dependent on her and her husband's paychecks, needless to say my mom tried to stretch every dollar. This meant a lot of the "No Frills" brand of products, from cereals to canned goods to bathroom products.
Once my sister and brother got to their teens they became super conscious of status symbols and bought whole hog into the conspicuous consumption ethos of the Reagan years.
So my sister decides she simply cannot do with the No Frills shampoo and conditioner or other beauty and hygiene products. She insisted she had to use some specific and more expensive stuff.
What was mom's solution? She bought the name brand stuff... Once.
Then she just refilled the bottles with the No Frills version. My sister never caught on and even told my mother that her hair etc. looked so good because she was using the name brand stuff.
Mom just smiled back.
While I think some brands are for sure of higher quality than some generic version, there is also a lot that frankly in a blind test most people wouldn't notice the difference.