Because they love Money!!! In my country Kuwait Money is more important than love for the women and the main base of marriage is Money for them,,,, out of money bye honey.
Generally speaking women are geared for security. Security can be physical, emotional or material. Money is just a part of the process that creates a sense of security.
As women are individuals, each one may place a different value on which aspect or combination of aspects are important to them. The lady who likes muscular partners enjoys the sense of physical security she gets from being in their presence. Another woman may feel emotionally secure with another type of partner and others relish the security they get from someone suitably capable of meeting their material needs.
Examined from a sense of 'security' pairings of individuals make more sense. No one bats an eye at the jock and cheerleader stereotype, it's simple and primal; or the rich kid surrounded by eligible partners, but the cheerleader and the nerd-boy from the science lab baffles everybody. On some level nerd-boy makes the cheerleader feel safe; if he's not wealthy or muscular then he is making her feel emotionally secure.
Understand after a certain point of speculation LIFE makes hash out of all of this. A woman who values the emotional safety she gets from a partner, may suddenly shift to requiring material safety when she has a child to care for. So the carefree guy she fell in love with suddenly becomes the deadbeat who doesn't have a job, plays video games all day and can't afford diapers.
All of these aspects of security can be twisted and warped in unhealthy ways. A person who values material security may step over the line and ruthlessly manipulate people to get what they want and becomes the ever feared 'gold-digger'.
All women arent the same,two important things that make personality for a man are money and a handsome face or nice body,there are some other things that make a man personallity too but I THING that these two are more important