Numbers 11:34 New International Version (NIV)
34 Therefore the place was named Kibroth Hattaavah, because there they buried the people who had craved other food.
If you allow desire to turn into greed, that is sin. If you feel it is your right to have something and you can think of nothing else, you are getting into a dangerous area. Do not allow something to affect your perspective or to preoccupy you to the point of becoming greedy.