Flamingo, I'm becoming upset as I read through the attitude you're displaying; I would have though people in the world were mostly better than that. Free markets and choices are just great when your economic circumstances empower you to choose the more expensive options where they are most appropriate, but that's absolutely no good to peoples whose circumstances limit their economic power.
Allow me to make this personal. I am presently a student in my fifth year of study, I would have graduated sooner had it not been for problems related to severe depression. I live off the small amount of money that is typical in this position; the vast majority of my income must go on day-to-day expenses and housing. My girlfriend lives in Helsinki. To see her regularly, and at more or less all times be looking forward to plans to see her, greatly improves my ability to cope with life in general. Flights to Helsinki tend to cost me about £100 return, which requires me to save as much as I can in order to make the trip several times over a year. Flights leave from London, and I must travel from Leeds. An open ticket is out of the question; to be able to afford that trip I must book in advance.
Supposing that my flight is delayed, you would see it as fair for me to be charged more. This seems perverse, because being delayed, and needing to use a later train, is out of my control, is not benefiting me, and is not something that I desired. In other words, I am not deriving any additional utility, and if anything am deriving less, from my overall trip. If anything, then, I should pay less, but I accept that the airlines avoid any sort of refunds. I certainly should not pay more, and it is within the railway industry's power to ensure that I do not. Besides any such reasoning, to pay more would be a very large hardship for me.
As for the question of alternative modes, clearly taxi is out of the question, I like many, view long coach trips - around five hours from Leeds to London -as a considerable ordeal. I suffer sickness of such journeys, and for that reason certainly cannot read or do anything that takes my eyes away from the window, and I have problems with sitting in the same position for that length of time. So as for many people, train is the only reasonable way for me to travel such distances.