My wife and I were traveling. Which gave us an opportunity to participate in Mass at at a small wood-frame country church typical of a rural parish. It had been recently renovated and expanded. including a fresh coat of some pastel, off-white color on all four walls.

This is a photo of a different church, but it shares the same beige interior.

As I knelt, praying after Communion, contemplating the Blessed Sacrament in the tabernacle; the crucifix hung above it on a vast expanse of identically bland wall rising up to the high peaked ceiling. Something was missing. Plain monochrome interiors may represent the authentic original style of country churches. Perhaps so. But the simplicity of early American churches was more a reflection of scarce resources at the time than of preference. When Catholics have had the means, they have turned to color. As soon as Americans could afford it, they built beautiful, ornate churches, like St. Alphonsus in Baltimore.

Even those gigantic gray structures of the medieval Gothic cathedrals once burst with colors. 

Cathédrale Notre-Dame d’Amiens 

They were drained of their vibrancy during the Protestant revolts and the French Revolution, but researchers and restorations are bringing the colors back.

Eastern and Southern churches never lost their colors.