I grew up in the Post-Vatican II era, but my mother still had us not eat meat on Fridays. It wasn't a big deal, but I thought she was strange. After all, no one else I knew gave up meat on Fridays except during Lent. Once I was an adult, I didn't worry about it, and Friday was no different than any other day of the week, except, of course, during Lent.
I managed to get through 17 years of Catholic education plus a graduate degree in Theology without learning that we are still supposed to sacrifice on Fridays. It wasn't until a few years back that I learned this and began incorporating it into my life. In 1966, the U.S. Conference of Catholic Bishops issued a statement that Catholics were to observe all Fridays as a penitential day but no longer were required to abstain from meat. You can abstain from something or engage in some "extra" work of mercy, but the call to sacrifice and do penance is still there.