I don't want to be critical of Barbra Streisand, especially without hearing out the other side, but why would someone of her known political persuasion favor the upper class with astronomical ticket prices at the expense of the middle class who will be priced out?
Even the Rolling Stones in the early 70s had a concert tour that included Madison Square Garden for a reasonable price of admission. I think that all tickets were acquired by lottery. Only lottery I ever won.
Since I believe that Streisand is not fond of touring, or even of live performances, it might take a lot of money to get her on board. Chances are that she distributes the proceeds to charities, or even political campaigns.