This is not surprising to me as I expect that the average pair of theology majors has more in common from the perspective of worldview and values, important things to share with a spouse, than the average pair of business majors.
Similarly but subtly different: you can also look at things that matter to people that are more or less common. Theology majors probably have more uncommon important values than business majors do. So it should be much easier to find a non-business major with matching values for business majors, than it is for non-theology majors and theology majors