Another seafood-hating Catholic here. Fridays in Lent for me has always meant cheese on toast.
The way I was taught it back in my Catholic school days, the Sundays within Lent don’t count as part of Lent. The liturgical season is still Lent, so the vestments at Sunday mass are still purple, Alleluia’s are still not used, and so on - but the fasting and other acts of penance are not required. (The nuns will follow this up by saying that continuing your Lenten denial on Sunday is “good for the soul”, to be encouraged, a sign of piety, etc etc, but I’m talking about the letter of the law here.) So waiting until after midnight on a Saturday would mean the feast was on a Sunday, and therefore “legal”.
Lent is forty days long, and if you count the days starting with Ash Wednesday and ending with the Saturday before Easter, skipping Sundays, you get forty.
As for the “middleman” business… near the church my family attended when I was a child was a tiny shop, in the living room of the owner’s house basically, which sold various objects to that church and a number of other nearby Catholic churches, as well as selling devotional items to the general public. The store was small and certainly nothing to get rich from, but then this was a small town without terribly many Catholics. Scale it up and you could have quite a thriving business.