Fadak was mentioned in many authentic narration in Shia and Sunni books. The narrations about Fadak in Shia books are so many that many scholars complied whole books on this matter.
Remembering the deceased and praying for them or feeding or reciting Quran or arranging a Majlis on their behalf is always good, whether it is done in yearly basis or monthly or weekly or even daily. Attending such gatherings is good specially when you are invited by a relative of a Momin friend to attend. You will have then the reward of accepting the invitation of your relative or a Momin as well as gifting a reward to the deceased. Wahhabism object on such gatherings because of their misunderstanding and narrow-mindedness.
Greed is described by the Holy Prophet (peace be upon him and his family) and the imams (peace be upon them) as a disgrace, like mentioned in the narration of Imam al-Baqir (a.s.): 'There is no disgrace worse than that of greed.’[Tuhaf al-’Uqul, no. 286]. Imam al-Hadi (a.s.) described it as ‘an evil characteristic.’[al-Durra al-Bahira, p. 42], and the Prophet (s) furthermore concluded that ‘Greed takes away wisdom from the hearts of the knowledgeable men.’[Kanz al-’Ummal, no. 7576].
It is described as a form of poverty because you are never satisfied with what you have: The Prophet (S) said, ‘Beware of greed for it is ready poverty.’[Kanz al-’Ummal, no. 8852], and a form of slavery because you are a slave to your lower self and its desires: Imam Ali (a.s.) said, ‘Greed is an eternal slavery.’[Nahjul Balaghah, Saying 180].
Imam Ali (a.s.) said, ‘The servant of Allah is free so far as he remains content. The free man is a slave as long as he is greedy.’[Ghurar al-Hikam, no. 413]
Imam al-Hasan (a.s.), when his father asked him about greed, said, ‘[It is] when you count what is in your hands as a source of honour, while you count what you have given away as a waste.’[Bihar al- Anwar, v. 73, p. 305, no. 23]
A greedy person is a person who cannot be satisfied and won’t look at all the blessing bestowed upon him. That is why he’s always in a state of poverty because he can’t make use of what he already has, as he is always looking for more, Imam al-Sadiq (a.s.) said, ‘Greed is worse than miserliness because a miser is parsimonious in spending what he has, whilst a greedy man covets that which others possess in addition to what he himself possesses, such that whatever he sees in the hands of others he wishes to be his – lawfully or unlawfully. He cannot be satiated, and nor does he derive any benefit from what Allah has granted him.’[Tuhaf al-’Uqul, no. 371, 372].
In reality it is a neglecting of your soul, and despite the greedy person thinks he “deserves” more, and that is the reason why he always wants more, he is neglecting his true being. Imam Ali (a.s.) said, ‘The person most neglectful of his own soul is the one who is full of greed.’[Sharh Nahjul Balaghah li Ibn Abi al-Hadid, v. 18, p. 84]
So where does greed comes from? Imam Ali (a.s.) wrote in his letter to al-Ashtar when he appointed him governor of Egypt, ‘Verily miserliness, cowardice and greed are all evil impulses brought together by entertaining a low opinion of Allah.’[Nahjul Balaghah, Letter 53], he further explained that ‘Cowardice, greed, and miserliness are vile traits that come together as a result of distrust in Allah.’[Ghurar al-Hikam, no. 1837].
Luqman (a.s.) said to his son, exhorting him, ‘If you want to attract Honor in this world, then cut off your greed of drawing advantage from what other people have in their possession; for verily the prophets and the veracious ones achieved what they did by cutting off their greed.’[Qasas al-Anbiya’, p. 195, p. ].