No, people simply non-magically build the building as they are conviced it is the correct thing to do due to their religious beliefs, as opposed to doing it because they are paid to do it with Gold.
If it's stricted to religious Buildings, sure. A lot of people donate Money/Gold their worship/religion Buildings, and contribute in building the buildings voluntarily (with their own hands sometimes). But I can't imagine why people should do that for other things, such as a ComercialHub Building. (perhaps it would make a little bit sense if they donate (being able to buy things with faith) under certain Situations, such as being attacked by an enemy with a different Religion)
This conversation has made me think of what would be the
ideal Tech/Civic Tree that would be both, realistic AND Gameplay balanced, and I think the optimal choice would be to keep the 2 Trees and not to rely on one Tree to uphold all the progress of a Civ. It would be neat to have the 2 Trees (Tech and Civic) interconnected with each other, as well as with some other Mechanics available in the Game, such as Loyalty, Ideology...etc.
What I thought of, is , for example, that a Tech in the Techtree can be boosted by an unlucked Civic and vice verse, aswell as by having met some criteria proposed from your Citizens (or some criteria they have to met themselves) based on their Ideologies and Loyalty.
The Boost can be triggere for the same Tech from mulitiple sources, and the amount depends on the Situation (if in war or having unhappy citizens the boost ratio will be smaller).
Same thing for the CivicsTree, except that it should have a bigger impact on the TechTree than the oposite. In return, Ideologies and Loyalty should have a bigger impact on the CivicsTree than on the TechTree.
And the Boost ratio should never be more than 70% (if boosted from all sources).
In contrast to the Techtree, the CivicsTree shouldn't be researched completely, you will have to choose between which way to go with, so upon choosing a root, you can't Go back and research the other ones. But the Civics on the other roots can be unlucked by certain Criterias/Situations, so you can still have the chance to unluck, for example, other Goverments, Policy Cards...etc.