When you see a queue for a restaurant would you consider it evidence that it's worth a visit? This type of thinking is pervasive in marketing, indeed all of human life. Some would say the it leads to the irrational exuberance of boom (and bust).
Such forces of attraction are inevitable in Interactive Democracy (indeed any democracy) and may attract people to vote on popular issues. A counterbalance to voter apathy. Just like the restaurant, once there, they make their own choice from the menu and vote as they please.
It's also a reason not to have running totals on the voting system, in order to avoid bias.