Some good thoughts on art and architecture and their proper role in worship from The Aesthetic Elevator.
As a Catholic in post-modern America, I see the same attitude in Catholic circles (more assumed than articulated) that was prevalent in the Baptist churches of my youth... that worship should be as plain as possible, and that highfalootin' art and architecture is a waste of money... "It could have been sold for more than a year's wages and the money given to the poor.". After all, we are supposed to worship Christ "in spirit and in truth", which means singing praise choruses in a strip mall or, in my case, a plain beige "worship space" (how prosaic is that term?) with track lights hanging from the bare girders.
I can't help thinking of C.S. Lewis' "men without chests", who were assumed to be geniuses because their heads seemed larger than normal, when in reality, it was their shrunken chests that made the heads look proportionally bigger.
A plain church building does nothing to guarantee a more pure or more "spiritual" worship. In a frontier setting, or by other necessity, true worship can be managed anywhere, and a beautiful thing it is. But a church building can also be seen, not just as a place in which to worship, or something that inspires worship, but as the product of worship... architectural worship, or a "prayer in stone" as it has been called.
Besides, I've heard too many stories of people being brought to hushed awe and reverence - even conversion - by the beauty of, say, the Pieta or Chartres Cathedral, to just wave them off as anomalies. Art can make a big impact on people's lives.
I can't imagine the kind of mind that could look up into the vast expanse of the vaulted ceiling of Notre Dame and think "What a waste of space". Waste is part of what makes art "art". Like poetry or music, it is useless for anything but making human beings remember their humanity.