If we read the whole account of Numbers 11 carefully, we can understand why God was so highly displeased with the Hebrew malcontents who were tired of His daily supply of manna and longed for meat and vegetables in their diet (verses 4-9). God gave them what they were asking for, thus bringing them to see how foolish they were to despise the good and sufficient food He had apportioned them in favor of that which they chose for themselves. In other words, in order to teach them a much-needed lesson, God saw fit to give the discontented rabble exactly what they asked for–rather than that which would be best for them. Such a huge number of dead birds would speedily begin to rot in that hot desert, despite the people’s best efforts to convert them into dried meat that could be preserved. There is little wonder that they began to suffer from food poisoning and disease as soon as they began chewing this unaccustomed food. In the end a great many of them died of plague and had to be buried right there in the desolate wilderness, at Qibrot Hatt'avah, “The Graves of Greed."
–Dictionary of Bible Difficulties