Usually the churches in malls are fronts for money laundering/drugs/prostitution/slavery/organized crime. There are a lot of these spaces for rent. Property owners really don’t care who rents as long as the check clears every month. The rent is usually fairly cheap too. A real start up church will rent space part time until they can save up enough funds to buy land and build. One church in my town rented an empty retail space for about 5 years until they had enough money to build their sanctuary and attached K-12 school. It is actually a very good school albeit small. Several neighbors have gone there and were very happy. Seemed based for a Christian school.