That might be logical, by some chain of reasoning, but it's not reasonable. To boycott them would mean to disconnect yourself from the internet -- impractical for many. Even if you live in a privileged zone with smaller ISPs available, your data still transits through these companies. By cutting yourself off, you forego giving them some miniscule amount of money, but you also disconnect yourself from news and the ability to communicate and organize with others who feel the same.