[sp332]

You can get a certificate covering multiple specific domains. https://github.com/letsencrypt/lets-encrypt-preview/issues/6...

A wildcard cert wouldn't cover both heroku.com and herokuapps.com anyway. https://en.wikipedia.org/wiki/Wildcard_certificate

[guipsp]

They said they'd rather not spend money buying two certificates.

[cpach]

Certs from Let’s Encrypt will be free.