I used to work for a call center around 2008 that had this same policy. I had to tell a supervisor (a kid given my age) that after I finished the call, I would go to the bathroom. I worked part-time (6 hours a day) so I was allowed two bath breaks of 2 minutes each and one break of 15 minutes. I don't remember being denied the right to go to the bathroom but getting the break allowed was a different story.
We had an union; not one related to telephone operator but one generic for shop employees. When I left this place, I went to the union to talk about the abuse employees receive there but I was told that it was my decision and my responsibility since I took the job in the first place.
About the humiliation and privacy infringement, I was not smart enough to complain when I was still there. I just left that place the day after they suspended me for using Opera browser. Two weeks later I got my first IT job.
As a side note, I worked for Teleperformance, that was hired by Accenture, that was hired by AT&T. I was assigned to high speed Internet support team, taking calls from Spanish speakers in United States. Oh, man... How much I loved that granny with no computer knowledge that translated everything to English to her computer savvy grandson (instead of the latter taking the call). Happened every day.
