It is indeed a lottery. The ticket website offers me a list or 20 (twenty) different single fares from Melksham to London for tomorrow morning - except that none but 4 (4 of the 5 most expensive ones, of course) is available.  And that is NOT yet taking into account disabled tickets, groupsaves ( 4 travel for the price of 2), forces rspecial deals, seniors, children,  blonde haired person railcards, rovers and britrail passes.

I saw a qoite that costs of providing certain services rose by over 3 time when the railways were privatised, due to a mixture of facors including extra coounting needs and the requirement to make as much money as possible for shareholder.  But that figure was NOT quoted for a First franchise.