Yeah it sucks. But I guess they need to keep something for 6S release next year.
And then next year they'll save something else for the iPhone 7 and so on and so on... This seems to be Apples strategy at the moment.
It just depends on when you jump on the train.. For me i tend to skip the middle road 's' models and purchase the generations with the biggest design change e.g iPhone 4, iPhone 5 and now the 6.