The picture is in a stadium, not an arena, this is probably in Texas opening for ZZ Top from the summer of 1974. Not sure if the Who dates were 1975, by that time Bad Co were a headline act in america and probably did not open for anyone. If the photo is from a Who show, then its Charlton football ground in London in early summer 1974. Bad Co were not on the bill for the 1976 Who shows in UK football grounds.