Rather than cut and paste, I will just comment on two points raised.

1. "Unsustainable" was probably the wrong word. What I meant was if a "surcharge of £1" was introduced, it wouldn't last, and would be £1.10 within a year and so on and so forth. 

2. Most concessionaries do not get all day free travel. However, there is an argument that they should. One of the main essential journeys is to/from the GPs and (for reasons someone in Primary Care might know), tend to be given morning peak appointments (except Mondays when Children are prioritised. Certainly, I have always felt that 0930 is ridiculously late as most bus borne commuters need to be behind their desk/counter etc before 0900, which with today's traffic means setting off well before 0800. Similarly, Schools start between 0815 & 0845 so the peak demand is well passed by 0930. Indeed, in eastern GM, peak hour service enhancements nowadays finish soon after 0800, wheras even a decade ago, it would have been 0845 ish.

I would ban free concessionary on Rail travel full stop. Partly because only a minority of concessionaries (mainly those in better off areas and/or who own a car) can access Rail and partly because such journeys are less likely to be essential. Not many local supermarkets or Health services have rail stations or tram stops. To make matters worse, because (heavy) rail tickets are not checked on boarding - if at all! - Concessionary travellers usually get away with boarding 10, 15 or more minutes before 0930.