I could see the possibility of it helping people give, or making it convenient, but what I have a problem is this:
Joh 2:16 And said unto them that sold doves, Take these things hence; make not my Father's house a house of merchandise.
Now I know Jesus is talking about purchasing Doves not ATMS, but I wonder how much we should mix worship, prayer, and banking.
Just a concern I personally have.
JMHO