Yes, because polls are really capturing the true opinion of half of 300+ million individuals, from the child to the elderly. As Mitt Romney learned somewhere around summer of last year, some polling data is not an accurate measure of real world opinion or action.
Not for nothing, but there's bound to be a large overlap in the type of people who believed the poll skewers that Mitt Romney was actually winning while ignoring many other polls, and people who believe that support for marriage equality isn't growing exponentially. It's the same group of people deluding themselves again.