I wrote about it a few days ago in response to Troy Hunt's FedEx post [0]. To answer your question, one of the reasons they don't use their own subdomains is th

I wrote about it a few days ago in response to Troy Hunt's FedEx post [0]. To answer your question, one of the reasons they don't use their own subdomains is that it's cheaper to delegate lots of support services to third party providers. Another is to avoid "polluting" their domains in the eyes of various reputation filters. [0] https://cybershow.uk/blog/posts/scamicry https://cybershow.uk/blog/posts/scamicry