There's nothing unscriptural about vestments. God commanded that they be used in the Old Testament. Look at Exodus 28:2. Catholic Feast/Memorial Days are days set aside to remember important people and events through the course of Our faith - Christmas, Easter, Pentecost, Christ the King, etc.
Luke 20:45 As all the people were listening, Jesus said to his disciples, 46 "Beware of the experts in the law. They like walking around in long robes, and they love elaborate greetings in the marketplaces and the best seats in the synagogues and the places of honor at banquets. 47 They devour widows' property, and as a show make long prayers. They will receive a more severe punishment." Deuteronomy 12:32 What thing soever I command you, observe to do it: thou shalt not add thereto, nor diminish from it.
Jeremiah 10:2 Thus saith the LORD, Learn not the way of the heathen, and be not dismayed at the signs of heaven; for the heathen are dismayed at them. 3 For the customs of the people are vain: for one cutteth a tree out of the forest, the work of the hands of the workman, with the axe. 4 They deck it with silver and with gold; they fasten it with nails and with hammers, that it move not. 5 They are upright as the palm tree, but speak not: they must needs be borne, because they cannot go.
When Jesus came to earth and died on the cross, the Temple curtain was ripped from top to bottom signifying that the ritual of human priestly mediation between God and man was OVER!