We tend to assume that dollars invested in art glass will be largely recouped when the home is sold. Add to investment value the concrete benefit of salability . To the degree that the addition of art glass makes a home more unique, prestigious and comfortable, it becomes considerably more attractive to potential buyers at selling time. This is a benefit that homeowner's can relate to. Privacy and obscurity are practical benefits as well.
Art glass can achieve both without sacrifice.
Improved insulation is the last on my list of concrete benefits. It won't always apply, but when the addition of art glass will improve on the insulating characteristics of an existing space, it becomes another meaningful advantage that needs to be communicated to the potential buyer. Now, let's admit that people who buy art glass windows for their home don't do so for any one of the above benefits, or even for all of them combined. But the concrete benefits above, carefully woven into your sales pitch, give the homeowner a tangible rationale to help justify their abstract desires. Arguably, all of these overlap and are really subservient to the single motive of self satisfaction.