Not sure how the finance works but if you can get a bus pass out of them just nod and smile through the interview get the pass then cycle in as often as you like. If you get an injury or illness it will come in handy.
Having just ploughed through the whole thread, including the silly bits, I'm amazed no one has made this point earlier.
This is about applying for funding, isn't it? Matt, it sounds to me like the woman was encouraging you to apply to get your £600 bus pass paid for. This sounds a bit like the experience when I had someone come round to my flat to assess my living situation when I was unemployed many years ago - the questions the DHSS woman asked me were very leading, designed to help me give the "right" answers and make sure I got all the benefits I was entitled to, not leave myself out of pocket.
She may also have been trying to put you off cycling - as others have said, 15 miles each way, every day in all weathers, sounds like a massive undertaking to a non-cyclist. That doesn't make her evil. Whether you cycle or not is entirely your call. I cycle to work every day myself, in all conditions (including high winds, snow and ice), so I know it's perfectly possible.
However, even for the hardiest commuter cyclist, there are some days when it may not be practical to use the bike for whatever reason (stuff to carry, other places to go etc), or you may be too tired or otherwise less than 100% (maybe you have a cold or something). And on those days, having a paid-for bus pass at your disposal would be very welcome, wouldn't it?
Apply for the bus pass, but don't feel obliged to use it every day.
d.