My understanding is that if a one button jacket of any type is worn, (suit, tux, etc.) that the button is just never buttoned, leaving the jacket open at all times. However, I'm looking at tuxes in anticipation of my fiance and I picking out the ones for his groomsmen this weekend, and I'm seeing quite a few one button jackets. In all of the examples in the Men's Wearhouse "Build A Tux," the one button is buttoned. Is this how they are actually worn, or are they just doing this to show the jacket closed so they all look the same?