That's exactly the point. The whole movie is a satire of consumerism, with Bateman's and his associates' constant struggle to one-up each other by wearing a better suit, driving a better car, even having the better restaurant reservations.
You might have noticed that all of the business cards read "Vice President" (a nice touch

). I don't know if this part is significant, but Bateman takes off his glasses when he goes to read one of the cards, showing that he doesn't actually need them to enhance his vision, but is wearing them because everyone else is.
One of my favourite quotes from the movie, which kind of sums it all up, comes from this dialogue:
Evelyn: Well, you hate that job anyway. Why don't you just quit? You don't have to work.
Bateman: Because I want to
fit in.