That is a Delta plane due to the seat-back pocket space shape, and considering most Delta flights in the United States have WiFi and in flight power plugs, it would be hard to specify what kind of plane they are on or where they are going. HOWEVER, they are not on the Lufthansa (Air India code-share) flight going to Frankfurt, as Lufthansa planes have different seats.
I would also like to point out the recurring motif of "going west" in the pictures. In most pictures, there is a arrow or object pointing west (such as the cow on the toy machine or arrow in the airport, plus the stationary plane was facing West) and also Las Vegas and the Target are on the West coast. Coincidentally, the plane that they are boarding in Robb's picture a few minutes ago has daylight coming in, which would be impossible if they were on the East Coast (unless the photo was taken probably 40+ minutes before posting). Maybe the Detroit picture was a reference to Delta's hub there, meaning they were for sure on Delta?
Who knows! I may be looking to much into this!