Well... for starters, you could have the wedding at your local parish church, limiting the expenses of venue rental (and maybe achieving some other economies of scope). If you have an extended network of friends and relatives in the area, they could assist with food preparation instead of hiring caterers. Some guests and relatives may attend the service with their own family and children, bumping the attendance numbers, but skip the reception or send the kids home. Coming in under $100/head should then be easily doable.

Of course this pattern is probably well-correlated with the "goes to church regularly" set and may indicate a level of serious commitment to marriage as "'til death do us part", to say nothing of other demographic differentiation.

This was puzzling to me too, especially because there was also a correlation with wealth.

I'm peripherally involved in the wedding industry, as I play in wedding bands. Granted, I only see the weddings where the couple hires live music (not necessarily expensive). But I get to observe some things about the couple, their guests, and how much they spend. All of this is just my biased anecdotal guess:

You don't have 200 friends, so if you've got 200 guests, probably 180 of them are someone else's friends -- distant relatives, business associates of your parents, church members. Perhaps simply being part of a larger network of supportive people helps stabilize your marriage. Especially if you didn't invite them to impress them with your lavish expenditure.

It's just my impression, but it seems like the folks who spent 20k, were the ones who were sold a big package, perhaps because they are young and un-confident about their social stature. They're probably spending someone else's money. I have rarely if ever seen anybody spend that much if they're older than 30 or even 25.

So it's quite possible that the same marriage will destabilize itself when the partners develop their own independent identities, i.e., "change" to the point where they're no longer compatible. Folks who are more comfortable with their own identity may also be comfortable saying "no" to the dozen or more people who are trying to fleece them as they navigate the wedding industry.

> "How can you not spend 20k or more when there are 200 or more guests?"

The short answer is: don't do the expensive things people normally do at their weddings.

It's not required to have a meal at a wedding; some American subcultures expect cake and punch only. It's not required to spend thousands on a single-use dress; my grandma still brags about getting her dress on clearance and being able to wear it for multiple occasions. It's not required to have thousands of dollars of flowers; at my wedding, my mother-in-law and her friends grew flowers in their gardens for us, and my sister's wedding (one week from today) will use the church's silk flowers. You can actually have a wedding with 200+ guests and still come in under $1000 if that happens to align with your priorities.

I had almost 400 guests at my wedding and it cost < $10k.

Venue: grandparent's backyard. Had that not been available a local church's community center would have worked (usually free or "free" with a donation of like $500).

Food: simple catered food. The wedding had a picnic theme (summer wedding) so we went w/ sliders and other finger foods. $8/head

Chairs and tables: Rented, but set up ourselves.

Photographer: Flew in someone from out of state. Much cheaper than a local LA photographer.

Dance Floor: Rented ($800) DJ: iPod with a playlist

Decorations: made our own decorations, borrowed strands of lights, etc.

It was a great wedding, wasn't terribly expensive and had a lot of guests.

I have a similar experience; my wife and I spent about $4000 on our wedding,and had about 150 guests, and it was a perfectly lovely (if not particularly fancy) ceremony. We got sandwichs, cheese & crackers, and fruit trays (plus some baked goods my wife and some friends made) for the meal, it worked out to about $2 a person, and no one left hungry. The reception was in the church hall, my wife got her dress off Kijiji (think Canadian Craigslist), and I just wore the suit I already owned (why waste enough money to buy a new suit on renting a tux? I looked sharp, and no one cares how the groom's dressed anyway). We bought flowers for the bouquets, but none for decoration (again, why? where does it make the experience better?) Photography was probably our biggest single expense, and we got that cheaply because my wife knew a woman who was just getting her business started and wanted to build a portfolio (our wedding photos are great, and we have digital copies of all of them we can make as many prints of as we want).

The short version is we planned our wedding with a mindset of "we want as many of the people we care about to be able to share this day with us as possible, and since we have a limited budget we're only going to spend it on things that make a positive difference in the day".

Is this 20k+ number in the original data? I might be reading it wrong, but it kind of looks like the opposite correlation is there.