You'll notice on my card, there's no last name or anyway to contact me except through the forum. And just for giggles and grins, my last name doesn't start with D. nor do I live in Portland, Oregon
I don't put these cards in a fish bowl trying to win a free lunch
But, I think folks need to do what they feel comfortable doing.
I've certainly seen plenty of site signs and spare tire covers blazoned with all kinds of personal information. And everyone see's that stuff in a campground or going down the road.