I'm talking about for those who already do PAY for the service but happen to not be at home when wanting to watch a game.
Not sure what you mean. Which service, cable or MLB.com? If you are home (assuming you follow the home team) then you can't watch the game on MLB.com. Ironically MLB.com is great for people who've moved but want to continue to follow their old home team. It's also good for people who travel a lot. But... it's probably never going to be much good for people who want to cut the cable and watch the home team in their homes. And this is by design.