At our respective village, every year each household performs an annual Rimdo (rituals) without fail. This was done with an objective to seek blessing from the protective deity and triple gems to shower unending blessing to the families till the next annual Rimdro.
Prior to the Rimdro, proper plan is put in place starting from consulting an astrologer for auspicious day till arrangements of all required items. Unfortunately one prominent item is the meat and substantial quantity is purchased. Some villager rears pigs and killed during the annual Puja. When you see people buy bulk meat like full cattle legs, pork etc, he is actually preparing for annual Puja.
On the Rimdro day, apart from consuming varieties of meat with families, friends, guest and ritual performers (Lam and monks), substantial qty is also offered as Tshok Sha (Offering meat) at the decorated altar that contain sacred statues thus contaminating the very sanity of an altar. Deities as a protector of all sentient beings will not come close to the place that offer meat for which they are the protector. If they don’t visit you what is the purpose of such offerings. Ironically, due to presence of flesh (meat) different types of roaming evils spirits may rush to the place and enjoy the feast with you and your families. So your annual Rimdro is actually appeasing evil spirits.
His Holiness the late Patrul Rinpoche sums up such evil ritual as under:
"If you perform rituals like the offering prayer to the protectors using only the flesh and blood of slain animals, it goes without saying that the wisdom deities and the protectors of the Buddha’s doctrine, who are all pure Bodhisattvas, will never accept those offerings of slaughtered beings laid out like meat on a butcher’s counter. They will not even come anywhere near. Instead, powerful evil spirits who like warm flesh and blood and are ever eager to do harm will gather round the offering and feast on it".
So please do educate your family, parents and AVOID placing of meat at the altar. Have logical sense if one is following Buddha doctrines.