拜金女 means Material Girl. With a average monthly salary of just 2,000 yuan, most girls living in Beijing won't be able to live a luxurious lifestyle. After deducting necessities like food, lodging, transportation, there is only a few hundred yuan left. It's certainly not enough to buy the Chanel No. 5, or the iPhone 4.
亲爱的 used to work as an office administrator when I first dated her. Her salary was about 1,800 yuan and at that time she did not stay with her aunt, but shared an apartment with her colleagues. She paid 800 yuan a month for the apartment. She realized that it was a waste of her time, so she quit the job, joined her aunt in the business, and move in to stay with her. I think this is more practical as she's just wasting her time if she were to continue working as an office administrator. 亲爱的 is earning about 4,000 yuan a month now. Not bad for a 22 years old girl in Beijing.
There are girls that can tolerate a simple lifestyle, but there are also others who are materialistic, and they would find other means to achieve their dreams. Having a rich husband is the ultimate way, but how by the time the guy is a high income earner, he's probably married. It would be easier for these girls to be mistresses for one or more men. Just last week, a Shanghainese girl added me in QQ, and we chatted. She's only 20 years old, and claimed that she likes to befriend older men. Although it was only the first time we chatted, she spoke like we have known each other for a long time. Anyway, here is a photo of her. I wonder how many men are subsidizing her living expenses?