They are totally worthless, except that if you lose big, you might consider pulling out of the race. That’s all it means. People actually have to pay $30 to cast a vote. It’s just fun now, because we’re finally talking about who is going to replace Obama. Woo-hoo! It’s almost over!!!
Actually the candidates pay for a big majority of the tickets. They put on big feeds for the participants who have the tickets and even provide transport.
All these "straw polls" determine is which candidate has the better campaign organization in Iowa. They also provide a candidate some confidence that they should continue the run if they are in the top 3 or 4. This "straw poll" is part of the Iowa State Fair sideshow.