Details are important. Really important. When gamers play a title and something looks off, they notice it right away. No wonder Capcom spent so much time recreating realistic guns and clothes. Capcom had to make the guns realistic guns because, as Takeuchi puts it, many Americans probably have held real guns. About the clothes, he adds:
...the footwear and gloves the main character wears are all based on real items. We contacted the makers of those items to find out all the little details that go into making them, that way players don't have a sense of the game being completely divorced from reality. And that's how we were able to realistically recreate the proper specs for the items used in the game. When you look at the trailer, you see the main character's clothing and all the fibers that comprise it.
We really paid attention to the details. We made it so that the fabric of his shirt actually gives the illusion of breathing like its real-life counterpart; it is also decidedly different from the heavier material that hangs down below it.
Finally! Gaming gets BREATHING SHIRTS. It's about time.
Jun Takeuchi Interview [Capcom IR]