The term "Blank Generation" or "Blank Fiction" is commonly used when referring to this type of literature. It is defined as "a range of American post-punk or transgressive fiction writers of the 1970s and 1980s." This can be linked to the Punk music genre which grew in popularity around the same time, and this eventually evolved into Grunge in the 90s.
This review from The Guardian shows a review of the book. It focuses on Clay, the main character, and admits that we are sympathetic with him and his repulsion of the scene in which he is living, and at the same time repulsed by him, demonstrated with the line "We both identify with Clay's disgust and find ourselves disgusted by him in turn."
http://www.theguardian.com/books/2011/dec/29/winter-reads-bret-easton-ellis - 2011 Review
It is apparent that the only change that seems to occur in the story is the development of Clay, from being part of the culture, to his growing disgust with it.
"The frictionless chill of Clay's world does touch us, planting a small seed of winter inside us that refuses to leave. Because Less Than Zero is not about Los Angeles, or the 80s, or drugs, or hipsters. It is fundamentally true. It's every time we turn on the news. It's every time we pass splintered glass on the road. It's every time we walk down the street with our headphones on. It's every time we close our eyes and go to sleep leaving the world behind. Maybe that's Less Than Zero's redeeming feature." This suggests that one of the key reasons that the story was so well recieved, was because there was an element of reality to it. The War on Drugs was real, and it is easy to imagine turning on the news and hearing any one of the events from this novel actually occuring in real life, and actually being repulsed by the offenders actions.
Early on in this book, we learn about the scene in which Clay is living. One of Sex, Drugs, extravagance and over-indulgence. A great example of his life is on page 17, where, with his Mum in the car, he casually mentions to one of his Sisters that the last time that he left his door open "you both stole a quarter gram of cocaine from me." This level of lackadaisical-ness shows how apathetic his Mum is, that she doesn't even seem to raise an issue with the fact her son had Cocaine, or that her Daughters then stole it from him. The abundance of drugs as well is startling. All of the main characters seem to have one addiction or another, or many, piled on top of each other, and each worse than the last. The parties are constant and the general lack of care about what happens at each of them shows the nature of their life. All on a break from their respective Universities and all "relaxing" with their friends.
Other than Cocaine, other drugs are mentioned and not much is thought of them. Heroin makes an appearence, and is the downfall of Julian, Meth gets mentioned and Weed is regularly smoked. Relating back to Youth Culture, it portrays them all as addicts, kids who behaved the way they did because they had the freedom to do so, and the money to be able to support it. Much like the Yuppie's of the 80s, the Drug culture is huge in the story, as well as their money, or rather, their Parents money (for the most part).
The story too has a major focus on the wealth of the characters. They all drive nice Cars and seem to think nothing of spending money on Clothes, Drugs, Food and whatever other expenses may come their way. It is a life that is very much abnormal, and almost a Rated R version of 90210. The varying degrees of cash they have affects their behaviour throughout the story, in particular with Julian. Having to resort to Prostitution to make some money.
The main culture that they all seem to have is one of the stereotypical relaxed California type. And when they aren't relaxed, it's for some other reason, such as Drugs, or a recurring theme of unwanted Pregnancies.
The end of the book takes an ever darker turn, with the raping of the 12 year old Girl, and Clay's refusal to get involved shows his character development. While everyone else hasn't changed, and doesn't seem to want to change, he has a desire to leave this life behind.