Nah, that's not what I'm saying. What I meant is that marriage, like everything else, is just a transaction. Both parties get something they want. It's like buying an apple, a car, or a laptop. You give something and you get something.
The problem is, marriage is usually very long-term. It comes with an ongoing opportunity cost. Both parties sacrifice things (freedom, money, other opportunities) to keep the marriage going. But what men get out of the deal from their ongoing sacrifice (sex, female companionship, great meals, and maid services) isn't compelling since they can easily get those things without being married.
It's like paying $100 for a slice of pizza and sitting down next to Round Table to eat it.
You are absolutely correct. Marriage is like prostitution. In fact, they are substitute to each other. Marriage is like sugar relationship.
The difference is, within marriage, or civil marriage, goverment is the pimp. Government is a very bad pimp. Government, rather than you or your spouse(s) make the rules. In fact, that's the biggest differences between marriage and other contracts. In all other contracts, you make the contract. Government just enforce. In marriage, government pretty much regulate the contract a lot.
When other people make the rules your interests tend to get screwed.
Marriage is so bad government have to prohibit alternatives. Prohibition of prostitution means you are not free to make your own sexual contract (though 50 shades of grey movie makes me rethink this)
Marriage rules in democratic countries tend to bankcrupt rich smart males. That is very important to keep rich men out of marriage market. So alimony, child support, etc, are set proportional to man's wealth.
That's not all. Outside marriage, you can still have sex with women. If she's not humping you stop paying and get others.
After marriage, you will pay her anyway whether she humps you or not whether she humps other guy or not whether she's divorced or not. You no longer have bargaining position to get sex. You may still get sex if she really likes you. But then again, if she really likes your cock, she'll probably hump you anyway outside marriage.