I'm not surprised by this.
I had a 120 person wedding nine years ago and it was $15k. It was not an overall extravagant affair, and I can easily see how a similar wedding, not in the off-season, would now cost a lot more. Here's an overall budget breakdown of what we spent:
Photographer: $1400
Flowers: $500 (just bouquets and corsages/bouts)
Attire: $1000 ($700 used dress, which I later sold, $100 veil, $100 shoes and $30 purse; grooms tux rental was free)
Ceremony fee: $600 (to church and priest)
Transportation: $500 (rented a van for the bridesmaids and a school bus to transport guests to and from the reception)
Music: $1000 ($500 for a DJ, $300 for a jazz trio during the cocktail hour and $200 for a string quartet for the ceremony)
Rehearsal dinner: $1000 (dinner for 26 at a local restaurant)
Decor: $200 (centrepieces and a few vases)
Cake: $220
Venue/food/liquor: $8000, including tax and tip --> included lots of wine with dinner and punch during cocktail hour; remainder was cash bar, which is socially fine in Ottawa, though I understand this is not the case elsewhere)
Remainder was on things like hair, makeup, nails, gifts, etc.
In retrospect, I can see how some of these things are completely non-mustachian, but they were also the best prices I could find on these items at the time. 34-year-old me kind of looks at this list and sees a lot of room for slashing, but 24-year-old me (who planned the wedding) didn't really know that some of these things were optional.
That said, I don't regret how we allocated the spending - more than half the cost was the reception, and that was for our guests, who had all travelled. And I decided to forgo a limo or other such nonsense in favour of making sure my guests had a safe and reliable way to get to the reception venue (it was a popular choice!). The music was important to me, though 2015-me would use an ipod in lieu of the shitty DJ.
I don't regret spending on the photographer, because I love my photos and still look at them. I also thought I did relatively well on attire, as I bought my dress for $700 and then sold it for $750 on consignment (I didn't get all that money, but it worked out). I also sold the veil for just about what I paid for it.
But it is so easy to see how the costs can just increase when you believe all of these things are necessities - we paid for a good chunk of the wedding ourselves, with both sets of parents voluntarily pitching in some money.