Customer service survey domain discrepancy?

I really don’t understand customer service surveys.
Recently, I got one from the Apple Store. It wasn’t spam. I knew that I had called their support department and they were all very cordial. But the email that came to ask about how it was? Didn’t come from a domain.
Now being very suspicious as it is, it’s interesting to note that no one would click on any address that doesn’t come from the origination domain right? We all know not to not to click on spam URLs and to go directly to the source to make sure that it’s what it claims to be. So why would you click on a customer survey link that for all you know could be going to some phishing site? Through e-mail no less?
Easy way to fix this issue? Set up a sub-domain where you run the surveys. Use the third-party if you wish, but have them set up their survey software off of the sub-domain. Then you won’t get paranoid people like myself thinking it could/might/maybe be a phishing site.
Baffles the mind. Really it does.