As the PP said - you buy the photo package and then you can add it to your PP account online at the following places that I can think of:
Chef Mickey's
Tusker House
1900 Park Fare (although last time we were there for b-fast they did not have a PP person there)
Spirit of Aloha
Hoop Dee Doo Revue
'Ohana
At CRT and Akershaus, the photos are free because they are included in the price you pay for the meal.
I don't recall ever hearing or seeing about PP packages at Crystal Palace, Garden Grill, or Cape May (all of which are other character dining places).
You're not paying for the PP service, but paying to purchase the prints of the photos and in addition to that, you get the code to add them to your PP account. I seem to recall that the photo packages were ~$20-25 but I can't really remember.