That's exactly it...
It would be LESS taxing on their side of things, more taxing on the user. However, it then comes down to meeting minimum requirements that are printed on the box, since you wouldn't need to worry about being connected.
They are out for any lil $$$ they can get (which is fine, they are a business). If, for example, my ISP was down because the wind blew the wrong way, no game for j0o! Just so many reasons that a user may not have a connection at any given point that could keep them from playing. Or, if EA decides to shut down the servers for the game, you have a neat paperweight
I hope it does work well and people enjoy what they paid for. I just hope that this trend does not continue and DEFINITELY hope it does not hit consoles.