They are immensely popular. But drive-thrus are still at the core of their service ever since the first location which was drive-thru only. That's one of many t

They are immensely popular. But drive-thrus are still at the core of their service ever since the first location which was drive-thru only. That's one of many things that can't be said of any of their upscale competitors, hence the fast food vs fast casual.