About half the money, give or take, is for above the line talent. So you have your actors, directors, producers, ect. They get paid in a percentage or in absurdly high amounts for films.
These people are also accommodate on set so production has to rent out luxury campers to house them for weeks or months at a time when on location.
Then they need to hire drivers and trucks to move those campers. Top tier stars can make demands on top of that.
I saw Jim Carrey’s camper once and it had an entire astroturf lawn on top of it, with a picnic table, with a vase with flowers on it. Don’t ask me why he wanted it, he just did.
Those costs are in addition to percentages given to the talent directly, which can be millions each for an A list celebrity. If this is a movie like Infinity War you have multiple guys like RDJ and Cumberbach and like four guy named Chris who could carry a blockbuster on their own and want to be paid like it.
Actors who aren’t the main cast still have to show up and get paid. Every random dude you see in the background is an actor who’s in it to get paid.
If you see a big crowd shot of like 500 people that means that’s 500 people who had to show up, go through makeup and costumes, and be accommodated and then be paid.
What you have left over has to pay for production.
At minimum it costs like thirty thousand dollars a day just to hire people to actually operate the cameras and set up lights and they usually work 12 hour days and have unions that demand good rates including overtime.
This is a very basic cost for a minimum crew for a single day where you get maybe a few minutes of footage done.
If you have those big 500 background days you need people to get people to manage those people.
If you have complicated shots you need more people for that.
If you’re out on location you need to pay the people who own that property. This can cost millions in and of itself if you need time and they know you have money.
You also need to pay an entire team of people to show up and get the location ready, which means emptying out whatever furniture is there and replacing it with your own stuff you have to buy.
These people are probably also working heavy overtime and have a union demanding pay accordingly.
If you decide that isn’t worth it then you need to get a studio and build the entire fake set from scratch, or pay a company to recreate it with CG, which isn’t cheap either way.
This doesn’t count the cost for pre and post production, which is two thirds of the process.
You have writers, editors, storyboarders, previz, color grading, foley, and a dozen other departments that have to do work before or after the actual shoot.
CG comes here in various phases and obviously isn’t cheap.
On a Marvel movie if you sit through all of the credits you’ll usually see like 8 other companies contracted out to do this and that and if you actually follow through and look up those companies they have big impressive shot breakdowns of what they did and a crew of a hundred plus people who may or may not also be credited.
If you sit through the whole credits of a Marvel movie you probably have thousands of individual names and there are probably three digits worth of people who didn’t even make that list. Those guys don’t work for free. This shit ain’t student film.