Musnad Ahmad 30:161

Sufyan narrated to us, from al-Zuhri, from al-A’raj, from Abu Hurayrah—Sufyan said: I asked him about it: "What is the food? The food of the rich?" He said: Al-A’raj informed me, from Abu Hurayrah: "The worst of food is the food of the wedding feast (walimah), to which the rich are invited and the poor are left out. And whoever does not come to the invitation has disobeyed Allah and His Messenger."