Why does Jerome translate the same Greek word as 'supersubstantial' bread in Matthew 6 but 'daily' bread in Luke 11?

Jerome is translating the same Greek word, epiousion, and he renders it 'supersubstantial' in Matthew 6 and 'quotidianum,' daily, in Luke 11, even though those are two different words that mean two different things. Why? Because with 'supersubstantial' he is trying to point to the Eucharist. But the real question is whether Jesus is pointing to the Eucharist in the Lord's Prayer when He uses epiousion, and the straightforward answer, without allegories, has to be no. He is pointing to our daily bread, the bread we eat every day to sustain our bodies; not everyone has bread every day, which is why we pray, 'Give us this day our daily bread.' If you translate it 'supersubstantial' you make it apply only to spiritual bread, and you cannot do that; and then trying to make up for it in Luke with 'quotidianum' is just playing with words, because it is the same Greek word, and you should not translate it two different ways, one spiritual and one physical. Jerome is not inspired; he was a great scholar but he made mistakes, and I do not think this was good of him; it is simply inconsistent. Scripture is not something you can play with, no matter how favorable you are to the Eucharist. The Lord's Prayer is not the place to argue the existence of the Eucharist; there are plenty of other passages, like John 6 or 'this is my body,' where that argument belongs.