Unfortunately, our story is fairly common, and from what I can tell from talking to others, here is the basic formula of how they maximize their profits day to day.
1. Comcast overcharges you. For a while you pay it, but it bugs you.
2. You call them up, and instantly hit barriers. They say "sorry, but our system can't do that" when it can. They say "we'll have our supervisor call you" and the call goes straight to voice mail. Sometimes a "Quality Assurance" supervisor calls you to ask how your talk with the imaginary supervisor went, at which point the original supervisor claims they tried to call you and you didn't answer.
3. Congratulations! You made it past the first few barriers. It is now more expensive for them to keep taking your calls than it is to actually fix your problem--you know, the one where they overcharge you ever month no matter what you do. They've tried to wear you down, and for most people this is where it ends: with the realization that you need Internet access and you're not going to call and cancel because they've made sure that there's no competition in your area.
4. So, now their tactics switch. They've tried to wear you down and found you to be tenacious and resilient. Now they start what I call the "bullshit phase" where they just admit their mistakes and tell you that their on it, and to check next month's bill to make sure everything is fixed to your satisfaction.
5. Except they didn't fix your problem, and if you're very unlucky, your bill could've even gone up. At this point they are admitting their mistakes, except the process of fixing your mistakes creates more mistakes and either another loop through the imaginary supervisor queue, or a real supervisor says "oh gosh" and promptly fixes your mistake for real this time.
There's a word for a group of people who continually try to take money which isn't theirs and then drag their feet when it comes time to paying it back: swindlers. We have been an uninterrupted customer of Comcast for over 10 years, and in that time they have never once had our billing right. We've had years go by where we just didn't have the energy to call every day and fight with them. They admitted they overcharged us for years and then ... wait for it ... gave us free HBO for a year after a week on the phone.
As a technologist, I absolutely need a fast Internet connection day-to-day, so I am at their mercy and they know it. The big incumbent carriers out there like Comcast are lobbying for laws to throw the consumers under the bus and eliminate what little competition they have.
This is why I say that Comcast is an abomination in every sense of the word. The world is a worse place with Comcast in it. Like some of the big banks, they tend to screw over the customers who can least afford their service. And for what? To please the stockholders?