Ask HN: Why do various services send email with the From header saying "via"?

To be more concrete, my company uses services such as Zendesk, Zoom, Zapier, and PayPal. For example, from Zendesk, we receive email with a "From" address of 'Zendesk Status' via [the alias for info@myCompanyDomain]. The email is addressed to an email address belonging to my company. We already know that Zendesk is one of our service providers, so there is no need for them to say "via". Why don't they just use their own email address? Note that the "Reply To" email address is set to status@status.zendesk.com.