Valve did it with Steam, people whined and got over it. Now Steam is loved by millions. It is something new and people fear change, but EA is really going the wrong way about this. I was actually planning on buying Crysis 2 after getting my 590 from newegg, but now I can't because it isn't even on the store anymore for steam (And I only really wanted it to add to my collection, I don't enjoy the story of crysis at all and the MP doesn't interest me).
I'm a gamer of wide variety, so I play the sims as well so this is a massive issue for me. The Sims is one of EA's biggest games and it JUST got onto steam and started having the DLC released for it, if they were to pull it halfway, I'd be pretty pissed, not much that will do for me, but it would make me hate EA even more, luckily they make awesome games so I can't justify skipping out on the games.
If it's only available on Origin you can boast the "Oh I won't buy this game at all now!" but once your friends are all in TS/Vent playing the hell out of it, you'll cave, everyone does.