I know taxi pricing for longer distances is often fixed (or at least I think it is?) however I recently paid ~£9 for a 2.5 mile journey. So based on that paying £85 for 25 miles maybe isn't ridiculous? Plus when compared to local journeys, the company has to factor in the taxi traveling back to its usual location.
She was visiting F-i-L daily in hospital, so £170 per day was not viable.
They were on a coach holiday so had no car with them.
In the end she used the bus.