NRE gave me a fare of £18 (matching the ranger price), but both Virgin and EastCoast wanted £22.10! If a sooper dooper compooter can't/won't offer the best ticket, what hope that staff will?
The problem here lies in the fact that rovers cannot be purchased online as thetrainline and WebTIS know and so they do not offer it as a fare.
NRE offer it simply because the site does not sell tickets so does not know it cannot be purchased (or maybe it does...). If you select it and try to buy it off another site then it will not allow you, saying 'No fares found'.
As for staff offering the ticket as a cheaper alternative, then I'm not so sure. Correct me if I'm wrong but I believe, unlike the NRE site, TIS' do not list rovers in the list of results on a point to point ticket purchase screen. Rovers and rangers have their own screen and therefore, unless staff have very good knowledge about the cost and validity of rovers, they won't be offered, even if cheaper.
As for the morality of this situation. As it currently stands, I cannot blame staff for not issuing a rover when cheaper.
Say I turned up at Weymouth ticket office and asked for a return to Cardiff Central via Yeovil, coming back tomorrow. I am then correctly issued the £39.20 SVR.
Say the customer behind me then wants a return to Cardiff Central via Salisbury also coming back tomorrow and is then 'incorrectly' issued a £41.10 SVR as opposed to a £40.00 3 in 7 FOSS.
It would be too much of a pain for staff to input things into two screens to determine the cheaper fare rather than just one. It would take twice as long, and if there are substantial queues then it will cause more problems than good, especially with such subtleties as the one I just highlighted!
If this is indeed against the impartiality regulations then it is something to be raised with ATOC, and something that they should work with the TIS' manufacturers to develop a solution to - even if it is in the same way as NRE brings up results.