Because not everything on this green earth uses HTTPS and SSH.
Examples:
(1) I want to implement a SAML consumer, and per the spec, I need to verify signatures. Crypto.
(2) I want to use a client-side cookie so that users can remain authenticated in the current browser session. Crypto.
(3) I want to issue a URL with a signed assertion that the owner of the content has granted permission to access it. Crypto.
Asymmetric encryption is not the be-all end-all of cryptography.
Because not everything on this green earth uses HTTPS and SSH.
Examples:
(1) I want to implement a SAML consumer, and per the spec, I need to verify signatures. Crypto.
(2) I want to use a client-side cookie so that users can remain authenticated in the current browser session. Crypto.
(3) I want to issue a URL with a signed assertion that the owner of the content has granted permission to access it. Crypto.
Asymmetric encryption is not the be-all end-all of cryptography.