Think of how stingy you are with your money: if someone on the street asks for $10, you're not giving it to them. There's no way you're giving a 30% tip for a normal dining experience. And so on.
想想你在花錢上是多么的吝嗇,如果有人在街上問你要10美元,你是不會給的。普通的一頓飯要收你30%的小費,那也是沒門。諸如此類的事情還有不少。