Fiance not wanting typical marriage! HELP!!?

My fiance and I have been together for a year and a half. Known each other for 3. We're best friends, wanting to get married, have children etc. My family is very christian, and very staunch in the ways of there church. The problem is this; my fiance wants to get married very simple, IN THE COURTHOUSE! And have a fancier reception. My parents are already pissed that I'm not getting married in there church, and when I tell my fiance this, he just says that I'm a big girl now and to not worry about my parents and what they want. So I guess my question is this - how do I keep everyone happy? Do I need to put my foot down on certain things and listen to what I want and then plan it that way? BUT my parents would be helping out with the reception financially! That puts a big problem in the situation. I feel like if I don't do it there way, they won't help.