Rogers uses those DoD IPs for its internal use. Who knows why.
18.104.22.168 is a multicast IP address, so it's not addressed specifically for you: »en.wikipedia.org/wiki/Multicast_ ··· _address
I wouldn't worry about it. Similar multicast is used all the time for Apple's Bonjour traffic. I'm sure there's also network monitoring traffic that would appear as strange if everyone closely monitored firewall logs.
If you're paranoid, pay more attention to inside-the-network traffic, since that's where an attacker or virus might be actively sending data back and forth that you care about. Outside the network should be mostly quiet pipes to Rogers' facilities.