I witnessed this multiple times at the Eiffel Tower:
Someone (possibly an adult, possibly a child) will come up to you holding a clipboard, and ask in mediocre English if you can sign a petition for handicapped access. “What?” you, think, “France has no handicapped access to the Eiffel tower? That’s outrageous! Sure, I’ll sign.”
Well, they hand you the clipboard and there’s a column for your name, your nationality, etc.. and then a column for the donation. “Uhoh,” you think, “Does ‘petition’ mean something difference in France?”
It doesn’t. They want you to think you accidentally agreed to donate money, and will act offended if you refuse. If you do give them money, none of it is going to go towards helping the handicapped.