Mouse House and Rules on Private Property
While 1A prohibits government punishment for exercising religious freedom, Title VII of the Civil Rights Act prohibits an employer from discriminating against candidates and employees exercising that right. However, just like the ADA, there's a "reasonable accommodations" test.
Back to the subject at hand...
Disney has a right to set rules for guest behavior on its property. Violate those rules, you can be asked to leave and be prohibited from returning, either for a specific period of time or permanently.
Just because TDO hasn't always enforced the ban on unauthorized 3rd party commercial activity on property doesn't prohibit TDO from enforcing it now or in the future.