Actually I have a friend who has been in this business for 15 years. She is very smart and a great speaker but without higher education and this was a great way for her to move up and make good money ($70,000 - $80,000/year when she was doing well.) She also educated herself on law/case law that helped her when talking to people. She is definitely not a jerk; she is very reasonable and was able to reason with people over the phone. She also did quite a bit of "research" on the people so that she already knew of ways that they could pay. She also has a great "phone voice" which I think helps with this job. Her strategy was to work with people and get them to agree to pay what they reasonably could. Having debt is not fun, and she would try to find the best way for the company to make as much. But she also made people want to pay. She thinks that in a way she is helping people. The alternative is them being taken to court and/or going bankrupt if/when they don't pay. And she needs to feed her family.
She never broke the law, however. It would be hard to work for a company that did that. As for the resume, if you can back up your achievements, I don't see how working for this company would be worse than having no job. Especially if you are successful at it while still being nice.