@dlowan,
I've done telemarketing, years ago while in college, or later when I needed some fast money and had some free evenings or weekends.
I had the ability to turn the area of my brain off that cared if I was annoying people. When you're doing it it's just another number you're calling.
I've also done survey taking, and the general attitude of the people answering the phone wasn't any different from those who you were trying to sell something to.
In fact, I appreciated someone who hung up on me, or said something profane more than those people who were trying to be so nice and wasting my time. Especially when they would let you go on with your entire spiel. You get paid extra when you sell something, so if you're not buying I want to move on to the next call.
I'm sure a number of people here have done such work, and maybe their experiences have been different, though I doubt it.
The typical phone room is not full of desparate people. Most people are doing this part time and or short term. It's college students, moms, seniors and people wanting to put together a few extra bucks. They are really not thinking about you too much, they're thinking of their classes, kids, friends, where they need to stop on the way home. There really isn't anything to think about regarding your job. When someone you called says something they find incredibly witty to get you off the phone, it's only about the 10th time you heard someone say it that night.
If you are desparate, and sensitive like you really feel bad that someone told you that you're interrupting their dinner, you aren't going to last more than a day or 2 anyway.
That phone call was funny, but if I'd been the telemarketer I'd of hung up within the first 20 seconds and gone onto the next call.