Would those parents be okay with it if they knew you were going to masturbate looking at those photos for years? Probably not, parents can be real squares about things like that. Imagine a toothless, filthy hippy with incontinence, wearing a dress stained with his foul excretions and other, unknown sources, lumbering up to a family and asks to take a photo with the daughter. Who could say no to that? Another masturbatory fantasy. If I were that parent, I'd look for a cop.
Bonus points if the horrible and obviously crazy hippy demands you call him Ma'am or Tommie because he's such an obvious lady.