For me it is quite simple, if i did not have my free 48hr boxes of which i have 16 and ability to buy tickets at 75% off the standard walk on fare, i guess i wouldnt travel by train.
I would probably use a coach instead, maybe longer journey time but far cheaper.
As a active employee who started before 1996 i have my sort of free travel perks (i pay tax on them so they are not entirely free), as an employee of a Transport for London company i also get a staff oyster card. My wife also gets both. Should i leave the industry or worse be dismissed i lose all travel perks, should TfL stop running the company i work for i automatically lose the TfL oyster card, i will keep my BR pass even on retirement.
This really is a non issue as rail employees who worked for BR reduces every year and currently they are in the minority bracket of current employees.