The world's full of people who'll blindly buy anything with SIM in the title, and they're going to buy this regardless of how annoying it is. However, there's also a market segment that buys good stuff, or things that might interest them. When you pull some shit like this, you're safe in getting the first group's money, but that's about all you'll get. This could easily cost them 10-15%, and I suspect that if you're an EA shareholder, that's pretty damned important; at least it should be. I imagine that in the video game industry, expanding your market is absolutely crucial.
Furthermore, by pulling something like this, you're opening the door nice and wide for somebody else to come along and grab that market share. At this point, I don't think anybody's going to be able to do something SIM related better than Maxis; they kind of wrote the book on it. But if Maxis/EA take their customers for granted, a new franchise won't necessarily have to be as good to make up for SIM's shortcomings.
In the end, EA will sell this as a success story. The 10-15% market share they didn't get they'll write off to piracy. However, over the long haul, it might well be problematic for them. Other companies are doing just fine despite piracy, and EA continues to rest on safe, established franchises under the faulty assumption that the same people will always be there. Bad move. EA's a publicly traded company, remember. Disappointing sales numbers for a flagship title is the sort of thing that can really assrape a company to death.