Has there ever been a concerted effort to contact some celebrity
agents and suggest picture submissions?
Like:
Your client XYZ has an article on Wikipedia [accessed N times in the
last month, if that data is available], but no/bad photo. We'd be
happy to display a picture of your choice if you can release one under
a free license, e.g., cc-by-sa.
I'm sure many agents would at least try to pry a decent picture from
the hands of a photographer for this.
Magnus