A man by his very nature desires variety. He may live with suppression of this desire for decades, conditioned by religion and mores, but there is no doubt given a degree of latitude most men dream of another partner.
One Religion has recognized this physiological need for another partner and that is Islam. The reasons for polygamy in Islam and its acceptance by the clergy are different, but the net effect is that it caters to a sexual release of a man with another partner in the ambit of marriage. Islam permits up to 4 wives and divorce is much simpler. This does not mean that all Muslim men are polygamous and have more than one wife. Economic reasons will again dominate and in India despite all talk by vested interests the average Muslim has one wife. However the rich do exercise their prerogative and will have more than one wife. This privilege is only for the male and women are excluded.
One can say that in theory a man by being allowed to have 4 wives has an outlet for a relationship with another woman and this is sanctified by canonical law. In a way, it is an acceptance of a basic urge of man for sex with another partner.
Polygamy is an outdated concept, but it served a purpose. With the advancement in life in all spheres, one can say that polygamy has gone, but the desire of man for another sexual partner has not gone. This goes on and is a facet of everyday life all over the world.
One aspect that needs a mention is the de facto presence of polygamy in the Christian nations. In 1862 the US Congress passed a law banning polygamy. The worst affected was the Mormon Church, which believed in polygamy. Over the decades the men in the west have however got around the law passed by Congress. Men like Donald Trump and Larry King, divorce older women and marry a younger woman. They thus extend the fertility period of their lives, something which polygamy would have done. It should also be noted that there is very little reverse traffic and all circumnavigation of the law of monogamy is mostly by men.