Finish a meeting early and take an earlier flight or find a reason to have to change your travel plans before you go and your tightwad travel planner will hate them as well when they see the change fees...

If you need to travel to the same destinations a lot, look at flight passes. They are mostly Tango Plus or higher. They offer decent value, but more importantly, cost certainty. No extra cost if you need to travel at short notice, as long as there is a seat. And changing your flight is only $50 if I remember correctly.