Putting files on USB defeats the entire purpose of streaming in the first place. The entire point of it is to have instant access to your entire library at any location or on any device in your home. That is why it is used, and why it is important to people. Having to transfer your file onto a USB key, take it over to your TV, and watch it that way is not a replacement for this.
If I wanted perfect quality I would be watching the Blu-ray.
If I wanted to stream, I would go to Netflix. (There's also Popcorn, Crackle and other free movie sites). If I have to go through the trouble of downloading video files, it's just as easy to do it to my flash drive and insert it into my device (or my WiFi router for multiple viewing). Bottom line: to each his own.