Networking is not simple
Networking is never simple. Improper video processing is visible. Improper audio processing is audible. Both are detectable by the end user and neither can cause major security problems for the user.
Improper network implementations on the other hand can potentially expose private data, create more Internet worm sources as firmwares get hacked, or open up the home to use as part of a botnet. Proper networking is complex, and the decisions made have major consequences.
If you believe that networking involves just dropping an Ethernet PHY into a device, you're misinformed and should have a professional check your home network settings soon.
Before the rebuttals, even major vendors' Internet routers have been hacked and/or have firmware bugs that cause security or other compatibility problems. As an example, if my Yamaha receiver acted as a router for my television's hypothetical video on demand service, but didn't understand P-MTU, it might not be possible to download some content from some providers. This happens to be a fairly common issue with improperly configured routers already. How about firewalls? Security settings?
I'll stick to proper network connections for my networked devices, thank-you.