Hello, just replying to this thread as it's fairly recent, I'm not a regular commuter, but have become one for the period up to Christmas and New year, temporary work.
I travel on Southeastern trains as I'm going from Tunbridge Wells to Rochester, wanted to buy a 7 day season ticket as I'm going to be weekly paid. Was told by the person at the ticket office that I had to register for The Key, Southeastern idea of an Oyster card (which I do have an old one for using when visiting family in Dartford , some London buses go there, and getting the underground in London.,) so that I could buy anything other than a daily single or return. I just wanted to pay them for a ticket for a few weeks not have my details registered with them unnecessarily.
Does the Key actually save money or is it just them being awkward for the sake of it?
I'm not someone who uses trains a lot so buying a long time in advance isn't something I tend to do .