It is simple. It costs more to run a web server with traffic going in and out, the IT staff to keep it secure from the public, bandwidth costs, IP address, webdesign costs, domain names, etc etc etc. Than it does to store and run it on a private server in thier network sending a one way signal to you box.

Just think about it. This is typical cable setup

+---+      +---+       +---+  
|   |==>===|   |===>===|   |
+---+      +---+       +---+
server     Tap          modem
Head       box in
End        your hood
Now lets look at a corperate web server set up

+---+       +---+       +---+       +---+     and    
|   |===>===|   |===>===|   |===>===|   |===> more
web          Router     Hardware    FBI black
server                  firewall    Box
Head end               
The set up just above hasn't yet left the head end where the feed originates. This isn't even taking into account staff costs that go up for security, updating web design, costs in developing a pay for system and maitaining it.(you didn't think it would be free did you) If they didn't bill you there would be some way they are making money or else they wouldn't do it.

So you see it is a matter of money.
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