I find it amusing when it happens. My little cousin did it...her jaw dropped when she saw it on Thanksgiving, and goes..."YOU GOT A PORSCHE?!"
But then the opposite occurred with this girl I've started seeing. She saw it, her jaw dropped...and she said "You got a 370? Those only just came out!". And then my mental jaw dropped, cuz this girl knows her cars, and thats nothing but a bonus in my book.