Can I have a wedding at a Disney theme park or Disney resort without going through Disney's Fairy Tale Weddings program?
Not really. If you want to be married in a theme park or Disney-owned resort at Walt Disney World or
Disneyland, you must plan the event through Disney's Fairy Tale Weddings program.
Disney's theme parks are private property. If you attempt to hold a wedding on your own in any public area, you are very likely to be detected. Disney has plenty of hidden cameras and undercover security everywhere, and they actively seek out unauthorized weddings. When you are discovered, you'll find yourself unceremoniously removed from the premises.
I've been asked if it's possible to get away with a private wedding in one of Disney's hotel rooms or suites. Maybe, but I really don't advise trying this. You won't be able to get any catering (i.e. through room service) without being discovered. If the housekeeping staff notices something, it will probably be reported and this could ruin your plans. Do you really want to sneak around on your wedding day?
Only participants in the Fairy Tale Weddings program receive certain privileges, including the right to wear wedding attire at the Disney resorts and the ability to get professional wedding photos taken in the Walt Disney World theme parks (for an extra charge). Also, other than the exception noted below, it is only by using Disney's Fairy Tale Weddings that you can have Disney characters at your reception.
That one exception: the Downtown Disney hotels and the Swan and Dolphin are on Walt Disney World Resort property, but they are not owned or operated by Disney. Because of their relationship with Disney, if you have your wedding at one of those hotels, you can have Disney characters at your reception. However, you don't get the full privileges of a Disney Fairy Tale Wedding. Couples who marry at the Downtown Disney hotels or the Swan/Dolphin are not allowed to wear wedding attire at the Disney resorts and they aren't able to have professional wedding photos taken in the theme parks.