What about passengers with mobility issues that cannot stand for a long(ish) period of time and wish to at least maximise the chance of getting a seat? I know there exist priority seats but you have the same issue with staff not wanting to cause a scene/risk violent retailation when someone who is perfectly capable of standing refuses to give way to someone in more need than them.
My preference would be a compromise:
- No more than say, 25% of standard class accommodation reservable on any train.
- 2/3s or so of the reservable seats can be booked on a first-come first-served basis by anyone for a nominal fee, refunded if cancelled before departure, to discourage unused reservations.
- Remainder of reservable seats only available to reserve by Senior or Disabled Railcard holders and a companion for no fee. (Could also be reserved by ticket office/customer services staff on request for those elderly/disabled people who don't hold a railcard, or those with a temporary injury).
Anyone sat in the 'disabled/elderly reservation' seats who hasn't got a reservation should be expected to vacate them if the reserver shows up (and should be rightly shamed if they don't!).
- Rest of the train unreservable so that most people can just sit wherever they please without worry of being kicked out of the seat they're in.
That way, those planning a long journey in advance can reserve a seat if they want, but have to pay a nominal fee for the privilege.
Those who for age/disability reasons really need a seat can get a reservation if they need it, without having to compete with those above.
Everyone else without reservations knows which part of the train to avoid, can sit in the first vacant seat they find; shorter dwell times, less confusion and fewer arguments.
I fear we may be venturing into Speculative Discussion territory here though, as there doesn't seem to be any motivation from the TOCs to change. In the case of the recent XC unreserved coach changes, we're moving even further from this model!