The two main expenses are venues and food. When renting a venue that will accommodate 100 people and the food for them it easily gets to $10K-$20K. It’s like everything else, you get what you pay for. A cheap venue will offer little space, crappy bathrooms, dull atmosphere, and the worse crime possible is having bad food, bad food ruins everything. My wife and I wanted all of our out of town family to have a great experience and view of Dallas and we wanted them eat some great Texas BBQ food, compared to our friends ours was on a tight budget, just those two things cost us $10K and throw in alcohol it went to $13K not counting everything else. Every did love the wedding, venue, and food it was such a great experience for us and them and was worth every penny.