There's a problem that everyone from developers to accountants keeps running into. You need to send some sensitive data (passwords, financial spreadsheets, etc.) to somebody. How do you do it? Email? HipChat? Slack? A USB stick? All of these have drawbacks. With email or instant messaging, the sensitive data may be stored somewhere out on the Internet indefinitely. Are you sure Atlassian or Slack will never, ever get hacked? All of these have drawbacks. With a USB stick, you have to make sure to wipe the stick securely once you're done, lest you drop it somewhere and somebody with too much time on his or her hands and a penchant for mischief picks it up. Sure, you could use GPG, but try getting somebody who has never used GPG before to set it up and use it correctly, especially if their only email account is webmail.