This is not about wedding costs, but the mathematical likelihood of today's women seeing the wedding altar.
The ratio is quite simple; the more sexually promiscuous females are as a group,
the less likely they are, as individuals, to see the wedding altar.
Why is this?
Pretty simple. Marriage is a life-changing event for men. Everything has to be adjusted to accommodate a wife.
Every adjustment has a cost,
and some of those adjustments require a man to abort his personal dreams and ambitions in exchange for a wife.
1) A man who doesn't need sex, will probably never marry or date.
2) A man who needs sex, but can get sex without marrying, may never marry.
3) A man who needs sex, and can't get it without marrying, will likely marry.
4) A man who needs sex, and wants a particular female, and can't get her without marrying her, will probably marry her.
A man who won't date without sex is a #2.
A female who gets pregnant out-of-wedlock will be less appealing to most men, including the man that impregnated her.
PS, The leading cause of death for pregnant women is angry sperm-givers that don't want to be fathers.
Sadly, one group of males most likely to marry are (sometimes) fatherless males who look for a woman to support them,
as their mothers did, establishing a culture of the woman being responsible for the life of the male; a complete social perversity.
Chick flicks are written to make females believe that if she gives a man everything, pretty much all at once,
he will fall head-over-heels in love with her.
That outcome is fairly rare, but to some women, it seems reasonable.
Many females also think they have to compete with other women for a man's attention, and the way to do it is through promiscuity.
Only if the man is a #2. And still, no wedding altar.
As a young man, I spent enough hours in bar rooms to know that easy girls are often viewed as porta-potties for semen.
Sorry to be so blunt and crude, but women claim to want know how men think. .
See also: https://teachustruth.com/1_60_confirmed-bachelors.html
Eric J. Rose