Was considering of adding this in the Warning & Dangers but it was more of a cultural option for visitors so i thought not.
The locals have discovered how lucrative posing for photographs can get...
When you take pictures of the Kalashas, they'd generally expect a small price (between PRP5-10) per shot, which isn't that bad. If you consider it a moral issue, remember that it's just another honest way to make a living or to supplement their income.
Usually the ones asking for money are the younger girls.
If you request from the families if you're invited to a home/homes, they'd generally be happy to pose for you at no charge, and offer you cheese, bread and tea!
Favorite thing: The Kalash people are very different from the rest of Pakistan. They aren't muslim and, therefore, the women don't veil up.