As far as I see it, if someone created something with the intentions that it will be "art," that it will be viewed, and that it will cause a reaction, an emotional response (of any type) in those looking at it, it is art. If it makes you angry or frustrated, if it makes you think "who the hell would pay money for this piece of crap!?" then it is doing its job as art. Art fails when it does not affect viewers in any measurable way.
On the Mummert colored block pipes: Are they my style, do I want to own one or smoke one? No. I do think they're interesting, and if nobody pushes the envelope in what a pipe can look like, we won't see evolution and change. You may look at this and think, "where will THIS lead? No one is going to use this as inspiration!" and maybe they won't move forward from this, but it will probably influence someone to use parts of it, or it might influence a carver to use the spirit of it, the "a pipe can look any way I want it to look" aspect of it. A lot of fashion designers will submit really out-there clothing to shows, and though few people will buy those pieces, they will inspire the fashion world.
These aren't by far the wildest pipes I've seen. Look at Micoli's work. Or Bekler's crazier abstract meerschaums. Forst of all, they were weird. Second, people bought them and smoked them.