Even though Innersloth is well known, they're still indie devs, they have to get their money somehow.
They need money for:
Food
Servers
Paying their employees
Making Among Us VR
That's why it's not free
what do you mean with "Food"
Food costs money.
you literally said it 2 times. "Paying their employees" and "Food". because the employees buy the food with their own money