Comcast is essentially using your private residence as a corporate resource. They’re using your electricity. They’re using your Internet connection (although they claim they aren’t) and they’re opening up your private browsing to potential hackers. While Comcast will claim that these two streams are independent, there is nothing to stop a dedicated hacker from figuring out how to snoop data passing through the router. There is also nothing to stop someone from downloading illicit material, software, and other junk from your hotspot and then reporting you for theft or worse. Again, it’s all ostensibly secure, but, like all things, it really isn’t.