Demons are by nature crooked like snakes. Therefore, to distribute a share of the nectar to them was not at all feasible, since this would be as dangerous as supplying milk to a snake. Considering this, the Supreme Personality of Godhead, who never falls down, did not deliver a share of nectar to the demons.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
असुराणां सुधादानं सर्पाणामिव दुर्नयम् । मत्वा जातिनृशंसानां न तां व्यभजदच्युतः
asurāṇāṃ sudhādānaṃ sarpāṇāmiva durnayam | matvā jātinṛśaṃsānāṃ na tāṃ vyabhajadacyutaḥ
SB 8.9.19