Not entirely true. You can turn off the wireframe on the 3d window (not the grid)
Its not a well shown feature infact its hidden.
Ok what you do is this.
Start uvunwrap. Then look at top menus, pick "options" then "hotkeys". Find "rendertexturesmooth" assign a key to it. Then close the hotkeys window and press the assigned key and wala in 3d window no more wireframe over the model and textures anymore.
Theres lots uvunwrap can do apparently, just all needs assigning a hotkey to use.
Here is a example of how to do this btw. I assigned K here.