I think the main issue is that the Oyster card is *not* e-money, which
would have to be regulated by the FSA.


Plus perhaps competition issues. After all, the LT Museum is a charity
separate from TfL. So if the museum was allowed to use Oyster cards as
e-money then why not the Tower of London? Covent Garden Market traders?
or the Big Issue seller outside the tube station? (IIRC legislation was
needed to allow cooperation between operators to create the system as
that wd otherwise have breached competition law.)
--
Robin
reply to address is (meant to be) valid