In many of the physical sciences both Masters and PhD students are usually paid a living wage, do not pay tuition, and work double or triple duty as student, teacher, researcher. These students usually do not accrue additional debt beyond what was needed for their undergraduate degree (if any). Despite their importance to many parts of the university system such as instruction, research, and funding (NSF proposals that don't have explicit funding for grad students are D.O.A.), they can still be treated pretty unfairly. Given the hours they work, it is still most common for them to be on the books as part-time employees (0.49 full-time) which cuts off access to employee sponsored health care that is mandated under the ACA. In almost all cases they have no benefits outside of tuition payment.
I think grad students unionizing is a fantastic idea. They are in every way the critical grease that keeps the capitalistic university system running. They should be able to protect themselves and have a stronger impact in how the universities are run.
The only concern I have is the huge turnover. Unions are most effective and most rationale when the members are committed for life. The longest any of these students could be there is 15 years (5 masters, 10 PhD). This would be very extreme. Most are looking to be out in 2-6 years.
Are there any other examples of unions for occupations that have mandatory turnover or term limits?
