Today is St. Joseph's Day and 100's of people, who aren't even Catholic will attend a St. Joseph's Day Altar and get thier Lucky (fava) Bean.
The "use" of Saints in "spell-like" capacity a very common thing in New Orleans and has been for centuries. Granted New Orleans is a very Catholic city but it is also a very Southern European city. We've had our fair share of French, Spanish, Italian, Sicilians, Canary Islanders, Yugoslavians come through and their impact is not small. Combine this with the African influences and you get a city where even those of German and Irish ancestry know about St. Joseph (patron saint of carpenters - help me sell my house), St. Anthony, and St. Ann (St. Ann, St. Ann send me a Man). It's cultural as much as it is "religious".
The Saints are Catholic. The Ways are not necessarily Catholic and were carried here primarily (not solely) by Italian immigrants. Saints and New Orleans are deeply cultural and have a links to ancient Pagan ways. It is this veneer of modern over layers of the past that gives New Orleans much of its appeal and mystery.
Also check out the City of Spirits & Italian New Orleans, German New Orleans, Irish New Orleans DVDs from WYES New Orleans' Public Television