Why there is no free Display Dock offer for Lumia 950 owners?

Why would Microsoft offer a new Display Dock to 950XL owners and not for people like me who purchased the 950 model. I don't want to hold a 5.7" Phone daily, just because of the free Display Dock offer. (I guess most people ordered the 950XL for that one?)

The Lumia 950XL has benefits enough for $100 extra:
-5.7" display
-Gorilla Glass 4
-Qualcomm Snapdragon 810
-3340mAh battery

Still pity because I don’t want to spend another $99 just to try the Continuum feature. Colleagues asking me about the feature a lot, but cannot show it to them. A missed oppurtunity if you ask me!

Expect a personal review for the Lumia 950 soon. (and hopefully for the Continuum feature at a later time)