...There is a tremendous bias against any glazed art in many of the larger galleries, to the point where some will not even consider any art with glass...even museum glass.
In my limited experience, money is not the issue. The issue has been described as "visual value", on the theory that
nothing should come between the art and the viewer's eyes.
By the same reasoning, we should enjoy the visual beauty of nature through our windows at home unencumbered by glass. Consider why your home's windows are equipped with glass.
The "visual value" of art unprotected by glazing will steadily diminish from its initial beauty to eventually become dull and ugly -- unless it is immediately dashed by accident. Even if the owner manages to keep a painting free of mechanical damage, such as abrasion or puncture from routine handling and housekeeping, there would be no protection from environmental changes that stress the fibers of all things hygroscopic, and no protection from the ravages of light. And then there's the issue of soiling. There is no way to avoid the deposits of airborne contaminants and soil on unglazed art, so a para-conservation industry has been developed for the purpose of cleaning, repairing, and refinishing paintings that have been damaged by soiling. At best, cleaning and re-varnishing an oil painting is an invasive and risky process, but how do you clean a watercolor?
All of that detriment is easily avoided by the glazing they disdain. What's wrong with this picture?
The art experts, who are generally gallery managers and often the artists themselves, choose to ignore the intrinsic value of the artworks they claim to appreciate. Their primary interest is monetary, so their concern for the art is only momentary. Regardless of price, they do not care how long the art lasts after it is sold, even though they may promote it as an investment to trusting, but unwary, collectors. The arrogant disregard of these 'experts' for the safety and longevity of the art they create or sell, and for their customers' investment, amounts to shameful irresponsibility.
Buyers, please beware.
Of course the framer's job is to provide the goods and services customers require, so the glazing decision rests with them. But please, let's respect our customers enough to recommend proper framing with glazing, and help them make the decision based on information, not ignorance. After all, they will not know unless we tell them.