I'm lucky enough that I don't have to deal with Comcast for my internet/cable services -- I have the fortune of working with the evil one known as Time Warner Cable -- but the customer service horror stories chill me to the bone. One unfortunate customer recorded his phone call of Comcast backing out of a set price, despite audio proof that they agreed to the price months earlier, because -- they're EVIL! Mwahahaha!
Even when the customer service rep agrees to give him the previously agreed upon price she will only do so with a downgraded speed. Because Comcast is a crafty s.o.b. and always has an excuse ready to go and at no point will admit a fault. They. Will. Not. Crack.
They may treat their customers like prison bait, but it's important to remember -- they understand your frustration.