Many people including me used to think that low competitiveness of a keyword will lead to low paying with cpc but when i had a look at google adwords blog they have clarified it that low competition on a keyword does not mean that it will be cheap. Competition is just one of the variables that determines your actual CPC. The price you pay for a click is determined by the quality score for this question.

If your keyword has a low quality score in comparison with other ads on that page, you will find that your actual CPC is approaching maximum CPC, although there is little competition for that keyword. Keep in mind that you never exceed your maximum CPC for clicks, but low quality score.