Question about the movie 'Juno'

Rose • Fiancée & Mommy

I was watching Juno yesterday, and a bit of it confused me (think it's cus I'm from UK)

She finds the couple to adopt her baby and then goes to meet them...

But when she says in front of the couple that she found them in the Pennysaver, the woman looks really shocked/disgusted and says "you found us in the Pennysaver?!"

Surely they would have known that this is where they were advertising?

Anyone able to clear this up for me ??