@Tutanota
1. Having multiple accounts for free. Can't use Tutanota anonym, if you can't create new accounts anonym, seperate from your other accounts; if you can't create throwaways.
2. Having an (easy) (free) way to (bulk) export email from Tutanota to your own computer, to be stored years from now when Tutanota might (will) not be around. In a standard format, that normal email clients can manage. Unencrypted (you can encrypt it manually). To really own your emails, not just have them in a cloud.