Because they give up their First Amendment rights in order to get kickbacks from the Federal Government and their members can get tax deductions on their donations...

As a result of the COVID-19 outbreak, the Treasury Department and the Small Business Administration have loosened restrictions on many of their lending and grant programs to include participation by churches and non-profit organizations.

For the purposes of these programs, churches are considered 501(c)(3) organizations and are directed to claim this designation on their SBA application, as long as they meet the following requirements:

• the organization must be organized and operated exclusively for religious, educational, scientific or other charitable purposes;

• net earnings may not inure to the benefit of any private individual or shareholder;

• no substantial part of its activity may be attempting to influence legislation;

• the organization may not intervene in political campaigns; and

• the organization’s purposes and activities may not be illegal or violate fundamental public policy.

Note that the entities administering these programs – including the Small Business Administration and lending institutions across the country – are currently facing a significant influx of applications.

https://sewell.house.gov/sites/sewell.house.gov/files/COVID%20Fact%20Sheet%20for%20Churches.pdf