When fares drop after you buy, then what?

Q. Last week I purchased two tickets for $580 to travel from Savannah to Phoenix. Today I saw the exact same flights on the exact same days for sale for $240. Is there anyway I can get the difference back on my tickets, which of course are non-refundable?

A. You can get part of the difference back, at least. Only three airlines will give you a price drop credit in full (Alaska, JetBlue, and Southwest). But none of those airlines fly Savannah to Phoenix, so most likely you're flying on an airline that will charge a $150 "ticket re-issue" fee, which will be deducted from your refund. Doesn't seem fair, does it? Airlines change their schedules and cancel flights with no penalty, but if you change anything, you're charged a fee.