It's really not THAT different than any other fast food place in terms of the speed of service or the number of staff. Even the price ($6.95) was about the same as what a typical fast food meal costs.
So I think the "disruptiveness" has been a bit exaggerated.
The quinoa portion was reasonably generous and tasted pretty good, but I don't know that I would eat quinoa every day. I didn't realize that they had no meat options before I got there.
As far as whether this model will become more pervasive, I'm not sure. But even if it does, I don't see the big deal since they are not really that different from what's already there.
Now, if they somehow got the costs to be MUCH CHEAPER than existing fast food options (let's say $2.50 for a big bowl of quinoa), THAT would be a game changer.