Banī ghabrāʾ uses an association with earth and dust to designate the poor; it need not name a documented tribe of that title. Ahl al-ṭirāf al-mumaddad evokes the comfortable owners of broad hide tents.
Poetic phraseReference
Banī ghabrāʾThe impoverished, close to the earth
Ahl al-ṭirāfProsperous owners of spacious hide tents
Placing both extremes together asserts a social reach across classes.