Effectively it was a surcharge. I don't see it as anything different from signing up for a 'free' service but you have to give card details up-front. Then remember to cancel in time. Enough people forget that it can be profitable for these companies.
I did exactly that a few months later. Again I withdrew £100 cash abroad. But the balance would not be cleared until the end of the month, meanwhile I'm still paying interest. So I pay off the £100 early, except the DD is still set to withdraw *another* £100 at the end of the month. So it's cost me, temporarily, £200!
OK I will look into that. I tried applying for a Nationwide one, but got turned down (the b*stards).
This was a few years ago when the rules kept changing. I think at one time, cash withdrawals were interest-free in the same way as purchases.