This is not just some post-Vatican II thing. While my parents (my dad anyways...my Mom converted in 1959) only ate what constituted one meal a day and abstained from meat on Ash Wednesday and all Fridays, they also gave up something "personal" as a small individual sacrifice to God. For some reason, that unofficial practice carried over after the reforms. It's not some crazy post-Vatican II innovation, at least in my farmily anyways. The problem isn't the teaching, as the Catholic Church clearly teaches that one must abstain from meat on Fridays of Lent and on Ash Wednesday, as it always has, but in the inability of its clergy to teach it and to teach the benefits of it.