Back in the day, sewing, knitting, etc was part of life in order to keep your family clothed. No chain store specials back then. So yes, this was looked at as "work". The stricter Christian churches frowned on working on Sundays, or making anyone else work. So, that's where the "don't sew (or knit, or ride bikes, or play cards, etc.....) on Sunday ethic came from.
Now that most of North America is not adhering to the "old" strict Christian work ethic, anything goes on a Sunday. Now that most stores are also open on Sundays, shopping on Sunday has become a norm.
I'm not THAT old (honest), but I still remember when nothing was open on Sunday, not even the gas stations. You had to remember to gas up on Saturday evening if you were traveling anywhere on Sunday.
Sometimes, in this hectic era, I wonder if we shouldn't go back to the "day of rest."
Just sayin'