Speaking with a representative from Bud's Gun Shop today because I was unable to reset my password online and he claimed they have been unable to send resets to Comcast customers lately because they are seemingly being blocked. I had been asking for a reset for 3 weeks.
No. Comcast is not blocking emails with the word "gun" in either the subject line or the body. I just tried it sending from my Gmail account to my Comcast account. Works just fine. So if emails from that gunshop are not showing up something else is going on.
Then like I said, something else is going on. You might call Comcast security and see if there is some kind of blocking issue for that sender's domain------------------
Comcast Customer Security Assurance-------------------
Normal business hours (6:00 am to 2:00 am EST, 7 days a week)
1 - 888-565-4329
Taking a closer look, it looks like a number of people reported their messages as spam. Typically this means that the sender should audit their mailing lists because they're sending to people that no longer want those messages, and they use "Spam" instead of Delete/Unsubscribe.