I think it’s more precise to say that in the U.S., the feast of St. Joseph is a holy day, but the obligation to attend Mass does not apply. I’ve never seen it NOT celebrated on March 19. Since it is a big holiday among Italians, who usually make a sizeable portion of any Catholic parish (your ethnicities may vary, for comparison purposes only), there would be some unhappy people if they had to celebrate St. Joseph’s Day on March 20 or 21.
I doubt the Irish would like St. Patrick’s Day being moved around either.
However, I believe the celebration of the Feast of St. Patrick is optional for churches. Very few don’t do it because of the predominance of the Irish in most parishes. But all churches celebrate St. Joseph’s Day. I believe that is worldwide.
The practice of the Western Church has generally declared abstinence for “flesh meat,” and when the lists of critters were drawn up (several hundreds of years ago), the lists looked amazing like a grouping by “warm blooded” and “cold blooded” categories. Shrimp and turtles are cold blooded and have generally been considered outside the “meat” proscription for Friday abstinence.
As noted, however, the bishops and the national churches have always had a certain amount of latitude in defining “meat” for the cultures in which they operate. I have heard the muskrat story off and on for years without ever bothering to see if there was any truth to it. On the other hand, in some places turtles have made it onto the proscribed list because their meat is more clearly associated withthe “muscle” meat we find in cattle or poultry.
In contrast, the Eastern Churches have tended to have a different list that proscribes even fish, eggs, and olive oil. (The point in both cases, as Bricker noted, is that the church is looking to identify an action that will call attention to sacrifice without necessarily looking to get involved in a taxonomic description of “what you cannot eat.”
Citation please? While now I don’t believe in god, I was raised in a Roman Catholic household in the US (I was born in 1961). I never heard anything about abstaining from eating meat (outside of fish) on Fridays outside of Lent. (And of course also Ash Wednesday.) I just never heard anything as a kid that eating a cheeseburger in July could be inappropriate.