When did "free puppies" become such a headache?

Keep in mind that we're screening people carefully, asking them about their home, other pets, etc. but trying to find homes for a boxer female's puppies has gotten to be a headache! (We do not own the mom nor the dad)

All of the puppies are black with white on their chest and toes..........

"I want the one with the white on its paws."
"I want the black one."
"I want the smallest one."
"Are their tails docked?"
"Do you think the dad is a boxer?"

Really? These are FREE puppies. The pick up stipulations are "cannot be picked up until April 28th" - when they are legally able to go to new homes.

I have told interested persons numerous times we are not the mom's owner, we are not the dad's owner, I can't tell them apart, I can't tell the boys from the girl based solely on the pictures, they are first come, first serve, I'm not saving and picking and choosing them out as the owners have already given one away after I took pictures.........

When did "free puppies" become such a headache?