Some Mormon churches have polygamous worshippers.
Australian Christian Churches was created in 1937.
International Christian Churches was created in 2006.
Christian Churches Together was created in 2006.
American Evangelical Christian Churches was created in 1944.
National Association of Congregational Christian Churches was created in 1955.
New Testament Christian Churches of America was created in 1969.
Thousands of them
Orthodox Christian Reformed Churches in North America was created in 1979.
Orthodox Christian Reformed Churches in North America ended in 2008.
Union of Christian Evangelical Baptist Churches of Moldova was created in 1991.
Approximately 3800 Christian churches are in the US. This answer probably left off 2 zeros at the end. Most estimates of Christian churches in the US range from 300,000 to 400,000.
Christians are not allowed in Mecca, so there are no churches in Mecca.