zhōu mò xiǎo zhāng yòu mǎi le zuì xīn bǎn de píng guǒ shǒu jī , zhēn shì gè dì dào de guǒ fěn
Simon: 周末小张又买了最新版的苹果手机, 真是个地道的“果粉”。
Zhang bought the latest version of the iPhone last weekend; he really is a true "Apple Fan".
tā dōu bàn nián méi shàng bān le ,zhēn shì dǎ zhǒng liǎn chōng pàng zi
Xiao Lin: 他都半年没上班了,真是打肿脸充胖子。
He hasn’t worked for half a year. He’s going too far in order to make others jealous.
nǐ men nián qīng rén ā ,yě bú cún diǎn qián
Simon: 你们年轻人啊,也不存点钱?
Why don't you young people save any of your money?
cún qián gàn shén me fǎn zhèng yòu mǎi bù qǐ fáng
Xiao Lin:存钱干什么?反正又买不起房。
What's the use in saving money? We won't be able to afford an apartment anyway.
In Chinese, "果粉(guǒ fěn )" is short for "苹果粉丝" (Apple fans). Simon comments that Xiao Zhang is a true Apple fan because he keeps buying the latest versions upon their release.
Xiao Lin holds another opinion, noting that Zhang "打肿脸充胖子", which literally means "slap one's own face in order to make himself/herself look fat." Many years ago, when food was scarce, being fat meant that you had plenty to eat and thus made others jealous. The phrase is still commonly used nowadays, and is used when describing that someone "does something beyond one's own means in order to impress others."
Simon then makes a suggestion by questioning "也不存点钱" ( why not save some money?). The rhetorical question starting with "也不" can be used to make a suggestion. For example, "天都黑了,也不回家?" (It is getting dark; why not go back home?)
In the last sentence, "....干什么?" represents another rhetorical question and is sometimes used as a negative expression. In the dialogue, "存钱干什么" means it is not necessary to save money. Another example, "去那干什么?" means "there is no need to go there" and in this case also represents a rhetorical question. However, it can also mean "What are you going to do there?" if intended as a simple question. You have to judge the different meanings according to the context.