[sdflhasjd]

I also find that some services don't let you use their name in your email address.

Samsung is one I remember which wouldn't let me use [e-mail], I managed to get by with [e-mail]. Definitely one for the password.

Then again, we should be using unique passwords for everything anyway, so a password manage is a must regardless of how you handle emails.

[throw_away]

This also happens to some extent in real life. Often when I say that my email is "[e-mail]" it's met with a "well, if you're just going to give me a fake address…". At which point I have to explain 1) catch-all email addresses, and 2) yes, you can own your own entire domain name.