This happened yesterday, went to a local ski resort and after getting to the top of the mountain, I saw a lady carrying her Canon 5D with a wide-angle, lens hood, and a big softbox on top of it. I was looking for someone to take a picture of my fiance and I, she made herself aware she was capable of using my 30D.
Oh, actually, I am very often in that situations that I always have to take pictures of couples (or single Indians for some reason). They see my camera and think, wow, he will make us look good on the photo. Sometimes I feel like I take more pictures with other people's p&s cameras than with my own gear
I am never sure how those images come out in the end though... guess they are all very disappointed in the end