They don't have to but they choose to :) I think that's a very good thing that they (Hot Toys) are doing!
From Hot Toys:
Today we are pleased to announce the Hot Toys 1/6th scale Hulkbuster collectible figure is getting revamped with further highly movie-accurate features and designs, including fans’ highly desired feature to put in Hot Toys 1/6th scale Iron Man Mark XLIII collectible figure (not included) inside the Hulkbuster after removing the included Mark XLIII upper body; metal joints implementation in various parts of the inner frame; an all-new retracting helmet design so it is no longer needed to swap out the part and able to display the armor in different stages of suiting up, and updated gauntlet designs which further recreate the movie-accurate and highly detailed mechanical design of the gigantic machine’s powerful arm!
To facilitate all these incredible updates and phenomenal movie-accurate features that meet Hot Toys’ high quality standards, we are putting in our greatest efforts in the creation of this astonishing Hulkbuster collectible figure and the release date will be changed to Q2, 2017.
Once again we would like to thank our fans for the patience and support. Please stay tuned for the release of this truly stunning collectible figure that will surely become a remarkable centerpiece in your treasured collection!
Check out the preview pictures posted on my toy blog HERE.
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