My problem is that I love to cook GOOD seafood, so it's not really much of a penance. It was more of a penance back in the days when the apprentices of London petitioned the guilds to prohibit their masters from feeding them salmon more than three times a week!
I heard this in history class back in the 70s, and it appears to be true from a quick google:
From "The History of Fly Fishing":
. It is reported that the first formation of a trade union occurred when the apprentices of London sent a petition to the Lord Mayor praying for them to stop being fed salmon and asking for proper fish to eat like pike or perch. They must have been successful because legislation was passed in the early 15th Century that you could not feed your apprentices with salmon more than three times a week!!