That they just exist to make a profit. That is the point of a corporation. Many of them are also led by people who I find morally objectionable.
Luckily, the only way they can do it is by giving people a service they voluntarily choose. As a result, you don't have to begrudge them money like you would a group of robbers, or a despot. Just...don't buy their crap if you don't want to.
I think a big disservice kids are done is being told Robin Hood was "robbing the rich to give to the poor" as opposed to "stealing back unjust tax money and returning it to the people."