Good Question: Why Aren't Airfare Rates Fixed?The sub-zero temperatures have some people looking to get out of town for a bit. And there's a good chance the airfare they pay now could vary by hundreds of dollars in just a month from now. Travel expert Terry Trippler, of ThePlaneRules.com, says there are several variables that cause airfare to go "up and down," and make a fixed rate nearly impossible. "Number one ... airports pay different landing fees at different airports," Trippler said. "Different landing and take-off fees."