Those workers, who say they were fired for striking last week, picketed outside of a sold-out concert in University City on Wednesday.
Nearly half a dozen artists have canceled their shows in solidarity with the workers.
Those fired claim a change in leadership is creating chaos, and part-time workers have not been paid on time.
New CEO Joe Callahan came on board in April. He denies the accusations.
Callahan says the employees were let go for abandoning their jobs last Wednesday.