Okay, this doesn’t relate to an expression so much as strange punctuation.
I’ll give you two examples and I’d be grateful if anyone could explain this baffling usage, which appears to be a younger generation thing.
I recently sent a WhatsApp message to my daughter, asking if she’d like to come to a dinner event with me. Her reply was, “I don’t think I’ll have time?” What is the question mark doing there?
Later, in an exchange about drinking tequila, she wrote, “I never do salt and lime?” Again, what’s with the question mark?
These are, to me, statements and not questions so I’m puzzled as to the use of the interrogative.
Anybody else come across this?