The Filet-O-Fish is one of the more curious items on the McDonald’s menu in that it receives virtually no advertising whatsoever, yet still continues to be sold by the chain despite the fact that it seems like nobody ever orders one and it’s been a problem item for years for the company due to difficulty in finding a sustainable, tasty source of fish meat at the volume the behemoth needs, as well as the fact that it requires a separate fryer to cook in than their other items. As it turns out, they keep it around because the Filet-O-Fish is actually intended to be eaten by a very specific kind of customer- people who abstain from eating non-seafood meat for religious reasons.