The article is by Father Dwight Longenecker, chaplain to St. Joseph’s Catholic School in Greenville, S.C. (DwightLongenecker.com) and his blog is found at http://gkupsidedown.blogspot.com/search?q= where I read his post and followed his link to his article.
They wish to discard the religious concept of sacrifice because it seems primitive, superstitious and barbaric. Instead, they promote the idea that the Mass is essentially a fellowship meal. They bring forward the biblical concept of the solemn meal that sealed a covenant between two contracting parties, and they see the Mass as a newer form of the regular, ritual meals that the Jews celebrated.
The covenant ritual meal, they believe, makes for a better and fuller understanding of the Mass.
Along with this de-emphasis of sacrifice, they also see the Mass more as a reenactment of the Last Supper than a window into the crucifixion of Christ. By focusing on the Mass as a ritual, fellowship meal, they have inadvertently shifted the focus away from the cross of Christ.
I added the emphasis and italics on what I feel is the sentence that explains it all and is the crux of the matter at hand. Do read this entire article, it is excellent, especially if you are baffled by the authentic Catholic's emphasis on sacrifice.