I think one obvious problem with this proposal is that my definition of a 'good' seat includes 'not so many people sitting in neighbouring seats, and the people who are look reasonably present and aren't being rowdy or drinking alcohol'. How much I value a Window seat will depend on what the weather is like and how much work I discover I need to do (or how tired I am) on the day. These are all things that are impossible to determine at the time that I make a reservation. And off the top of my head, I can't think of many things that would distinguish a particular seat that would make me willing to pay to sit there at the time of booking - especially when I know that a fair number of 'reserved' seats are likely to turn out to be free after all when I board the train.
More fundamentally, this just adds to the complexity of buying rail tickets. I really don't want to have to worry about paying different amounts to get certain things. I'd much rather just pay one fare for the distance I'm travelling. I fear that rail tickets are getting closer and closer to the airline model, in which fares for the same journey vary so much, and there are so many hidden extras that you might not notice if you're not careful when you book, that you can basically spend all afternoon looking at different sites and flights to get somewhere near the best price - so booking a flight becomes a huge chore.
In the 70's as stated above a seat reservation cost extra if you fly you can pay a lot extra for a good seat or even for priority boarding or suitcases. In the US you can be charged double if your overweight so in this world of private companies franchising I am surprised they all don't do the add on extras to boost the take per passenger
Yep. And that seems to be a fairly recent phenomenon. I'm pretty sure that even two years ago, no extra charges were applied for any economy seat.
Incidentally, a month ago I flew to San Francisco with Virgin. When I was invited to choose seats, it turned out that it would cost me about £80 extra to choose the extra-legroom seats by the emergency exits. I decided that was too much and declined. When I actually boarded and had a chance to look at the seats, I realised that the extra-legroom seats also had much smaller tables, had no window by them, were right next to the toilets, and if you were sitting at them, you wouldn't be able to watch tv during take-off/landing (because the tv's had to be stowed away - a restriction that didn't apply to all the other seats). If I had actually paid for one of those seats, I would have been extremely annoyed, and be pursuing a major complaint with Virgin. I think that illustrates how different people's tastes vary, making it very hard for a company to judge what counts as a good seat that's worth charging for.