@AlpineSkier
It's an EU ruling,
EU forces airlines to advertise true cost of '99p' flights | Business | The Guardian
So, he picked the least used card available in the UK. He will have a problem if the Electron card disappears*, because he will have to make another form of card payment free.
* It is my understanding that Visa is replacing the Electron card with a Visa debit card with a different numbering system and pre-authorised. So it is effectively Electron but under another name/guise.