Oh yes forgot to say your last few lines... wanted to say but
just forgot.
Yes, all these things are actually a form of folk tradition. This
practise does not help the deceased... but rather we should put all
our effort in getting the deceased be reborn in Pure Land or at
least in higher realms. This is by dedicating merits to the
deceased, chanting (the deceased might chant along as well if
everyone chants around him), if best have a venerable speak to the
dharma to the deceased.
Things like food, or giving whatsoever to him, will only cause more
attachments and for a deceased person it would be best that we
should let him go detached from all worldly things, tell him that
everything will be taken care of, and it is time for him to leave.
If one becomes too attached to worldly things, it will impede his
rebirth and may in turn become a ghost.