No. Try websites like Travelocity, Kayak and Expedia . You will have much better luck.
Yes, if you buy them on Spirit, Frontier, or Allegiant you will save $20/person/direction off of the ticket price on the website. Travelocity, Kayak, Expedia and other ticketing agencies other than booking direct with the airline is more expensive, as these airlines charge an "external ticketing fee" of $10/person/direction.
Buying ticket at last minute at airport counter is the very last option to consider.
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