Given the current state of airline finances, I am not sure if United still empowers its employees to provide that type of commendable service.

If you read Herb Kelleher's book you'll discover that Southwest provides its employees with great latitude to effectively handle virtually any type of situation. I don't know if that philosophy is still in vogue at WN; but I do know that WN's walk up fares are capped at $309 one-way so you would never be gouged.