"You" who? Confederate officers? Baptist preachers? Republican politicians?
If people are willing to pay to subsidize an art, it's art. If no one is willing to pay and the artist demands government grants to make up the difference in his or her income, then there is admittedly a problem with the "art" definition - the individual becomes a welfare recipient. But the dancers discussed above aren't surviving on tax dollars - people pay well to see them.
As for college-level Masters Degree programs - any art or science requiring a sufficiently difficult program of study can be turned into one, provided there are students willing to pay to learn it. The existence of a Masters Degree in Dance doesn't devalue the Masters Degree in Chemistry being offered next door. A Masters Degree in Weight Lifting would not make sense because the skills required can be learned in a very short time - the rest is simply practice and repetition. And colleges do offer Masters Degrees in the broader field of Physical Education, which would encompass weight training.
That's why the anger has puzzled me. What these dancers are doing is capitolism at its best. Produce something (many things in fact) that people want to pay to see. And they do, and people pay good money for performances, DVD's, workshops etc
Maybe it's jealousy that we like them better than him.