Depends on the church. Some any bread or cracker is fine, others the wafer is prefered. I went to one for a while that only allowed Matzoh suitable for Passover.
Some churches have enough money to purchase it from outside. Many of those purchase it from certain convents where nuns make the wafers. Other churches with less funding have volunteers prepare...
- From a symbolic aspect, the way unleavened bread had to be made at the time gave the bread a distinct look. In order for it to cook properly, cooking through to the center, it had to be striped...