You're right, I forgot to even cover that part because I was focused on how annoying they are to me as a user, not necessarily as a service provider. I also forgot to mention how they train people to click on links, how my inbox now consists of dozens of emails per day telling me to either click to login, or warning me that I logged in.

I have my own domains for email so I haven't had the issue of someone else entering my email but I keep hearing from friends getting that.