Yep, old question. Because battery capacity is expensive (and heavy!), most carmakers have come to the conclusion that it's smarter to have just enough battery for 95% of the driving, and then cover the rest with either a REx (Volt, i3) or not at all.
Three years from now that might change, but TODAY, shorter ranges make sense. You're not just building a car to display at a car show, you're trying to build it at a price that people will actually buy.