"Strict Observance"?
I know a thing or two about sales & promotion and can assure you that this was poor and very lazy branding. Your whole value proposition is messed up, disjointed, has huge unknowns and potential supporters have no practical way in 95% of cases of getting to a Mass said by one of your priests.
If the theatre does not fill up, you cannot blame the audience.
I appreciate religion is not a business, but people are people. You ignore their self-interest at your peril.