Ate their donkey? Does it have cloven hooves? Nope. How about chewing its cut? Also no. Therefore a donkey is not kosher. Jews don't eat their donkeys. Also a donkey is a working animal. Eating it would be like eating your seed corn - you might do it in times of famine as an act of desperation when everyone is struggling for food.
I love arguing that Jesus' family had to stay in a stable because they were poor. The purpose for the census was taxation, so Mary and Joseph weren't poor - they were being audited. That usually leaves social justice leftists' heads spinning.
I’m too lazy to look, but I don’t think the gospels mention any donkey. Paintings and figurines should not be mistaken for the Gospel.