An Orthodox Jewish man, wrapped in a plastic bag in his airline seat, apparently did so because he was probably a Kohen who went to extreme lengths to make sure he would not be ritually impure if the plane flew over a Jewish cemetery.
Kohenim are prohibited from coming into contact with dead bodies, and many rabbis have taken the strict opinion that a Kohen may not ride in a plane if he knows ahead of time that it will fly directly over a Jewish cemetery. Many have ruled that if does not know of the flight plan, he may ride in the airplane.
El Al once agreed to change a fight trajectory to avoid flying over a cemetery.
The man wrapped in plastic, whose photograph first appeared on the Redditor site and later on the Gothamist site, apparently did not want to take any chances. By covering himself in plastic, he established a separation between him and impurities.
However, since he arrived at his destination safe and sound, it can be assumed there was a hole in the plastic bag so he could breathe.
Some readers of Redditor suggested that “plastic man” was making sure he would not come into contact with the woman sitting behind him, but that is doubtful since it is unlikely he carried a plastic covering “just in case.”
Or maybe he simply wanted some attention.