Or HaChaim on Deuteronomy 12:20/אור החיים על דברים י״ב:כ׳

1 כי ירחיב…את גבולך, "When G'd expands your borders etc." Seeing G'd had objected to the excessive craving for a meat-diet displayed by the Israelites in Numbers chapter 11 where we were told about thousands dying on that account, such a craving had been taboo ever since. Only meat which had first been hallowed as a sacrifice had been permitted to be eaten by the average Israelite during the last 38 years. At this point Moses justifies the new legislation which sanctions the desire to have a meat-diet by referring to the difficulty of making the meat first a sacrifice and having to travel to Jerusalem to do so. It is assumed that the craving will re-surface as a result of most people living a long way from Jerusalem. G'd specifically sanctions the desire to eat meat with the words: "you may eat meat in accordance with all the desire of your soul."