NFL chain gang members are usually college or high school referees.
Unlike college chain gangs, which are usually high school refs or some other people connected to the home team.
And high school chain gangs, which are either interested parents or guys from the JV team or somebody rounded up from the snack bar.
In the NFL, the official chains switch sides at halftime. In college ball, they are always on the side opposite the press box. The NFL uses a full set of chains on both sides, but in college football they just use a line of scrimmage marker and a first down strip on the other side. And in college football, the line of scrimmage guy on the opposite side of the field doesn’t move until the next play has started. He’s sort of the last resort guy.